Reddit mentions: The best aquariumhoods

Under 100 bucks will be a little tricky, I think I can get close but having to buy a lighting fixture/hood will end up pushing it over.

• 20 gallong Long aquarium (30 x 12 footprint) $32.99 @ petsmart(you might be able to find this cheaper with a glass top at a LFS where dollar per gallon on these smaller tanks is a little more common.
  
  Second Option 29 gallon - has the same dimensions and usually just a little more expensive--however, you might be able to find an all-in-one kit with a hood, heater, and HOB filter for about 100 bucks...if so, that's the way to go for sure.
  
  
• Marineland LED full hood 30"x12" $35.99 @ Amazon with free shipping.
  
  2nd Option - Nothing cheaper right now.
  
  
• Filter: Aqueon 50 $23.10 @ Amazon This gets even cheaper if you make your own filter media instead of using their cartridges. Aqueon are decent little filters, and for that price and GPH you'll have a tough time beating it.
  
  2nd option: Penguin 200 $25.49 with free shipping @ Amazon The penguin has more media options and more media volume even not counting the biowheel. But it is a much noisier filter. My true preference would be an Aquaclear 50, but they're just not on sale right now and we're on a budget.
  
  
• Heater: Aquatop 100W for $14.99 @ Amazon . Aquatop is a bargain brand so this is a bargain product. But it's cheap and comes with free shipping.
  
  2nd Option - eheim jager 75W heater $24.27 @ Amazon eheim's last and are very reliable. I have a pair that are over 6 years old and still work great. Spending the extra money here would be worth it if you ever want to perhaps use the tank for something else down the road.
  
  
• Thermometer - Going as cheap as possible here, and I always like the accuracy of an analog thermometer. $3.92 with free shipping at Amazon
  
  2nd Option - nothing cheaper that's anywhere near as close in the reliability/accuracy department.
  
  So, that puts my 1st option total @ $110.99 with shipping but without any applicable sales tax for a new set up. Now you can really find something on craigslist.org for cheaper often times, so it might be worth it to look around there--but a lot of that stuff i found is on sale currently so if you wait too long it would be gone.
  
  Now for the fish.
  
  
• I would go with a pair of convict cichlids. They will breed every 2-3 weeks and if there's nothing else in the tank they can put out 100+ fry. Now with this set up they're never going to get very big without a grow out tank, but they will never eat their babies and they're pretty cool fish in their own right. They are also hearty so if you take care of the tank they'll live for several years breeding like bunnies.
  
  2nd option - Guppy tank with 2-3 males and 12-14 females. They will match the convicts for numbers and like the convicts they are very low in Thiaminase (which is super important for predator fish). They are relatively hardy but I find them to be super boring. They will also eat the heck out of their own babies. But on the plus side they're a bit dummer and slower swimmers than the convicts and with several harems you'll have a nicer sizing pattern on the fry that do survive.
  
  Which ever way you go make sure to put a sponge or some panty hose over your filter intake to keep from fry getting sucked up. Also, always gut load with a good quality food right before feeding. Something like New Life Spectrum Cichlid Formula for the convicts. This will make sure the Largemouth and Oscar are getting the optimum nutrition from the live food.
  
  Now that it's all said, you can actually breed your own earthworms for about 10 bucks in materials plus compost [Here's how to do that](
  http://www.herper.com/earthworms/earthworms-culture.html) and your fish will appreciate the live food variety.
  Hope this helped!

Bettas can get along with a variety of community fish. Whether an individual betta does is up to the fish--they do have different personalities so while one betta may be mellow and be perfectly fine with tankmates, another may not take too kindly to other fish in his space.

There are a few things you can do to maximize your chances of success in keeping betta with tankmates.

One is to not pick any fish to go in with the betta that are very brightly coloured and/or have long, flowing fins, because the betta is likely to mistake this other fish as another male betta.

The other is to introduce the other fish first; if when putting the betta into his new home, the other fish are already there, he's more likely to just accept their existence, whereas if you try to add new fish to HIS tank once he's already settled in, he'll see them as intruders.

A good bet with bettas are corydoras catfish, in a 10g you could do dwarf or pygmy corydoras which are the smallest species. Since they're bottom-level fish, they won't really intrude much on the betta's space because most bettas are middle to top level fish. One thing to note is that if you get corys you'll also want to do sand substrate, since gravel can damage their barbels.

So here is a list of potential gear, there are a couple of options on some categories:

10 Gallon Standard Tank $10 in-store at Petco (Dollar per Gallon ends the 19th BTW)

AquaClear Hang On Back Filter $28 This is a little pricey, but it's probably the best hang on back filter on the market. It's more powerful than the other ones I've listed. Part of why it's so great is because it's very customizable, you can put your own filter media in if you want (the stuff it comes with is not bad though). Also it's really easy to clean which is a plus.

Aqueon Quietflow Internal Power Filter $14 A lot of people don't like internal filters because it's a bit messier to clean since it's fully submerged; personally I don't mind cleaning it and also because it's totally underwater I find it a lot quieter that most filters which might be a good thing if you're keeping it in your bedroom. I'd suggest not using the little cartridge it comes with and stuffing it with your own biomedia and filter floss, but it's powerful and compact.

Tetra Whisper in Tank Filter $11 This is the only filter here I don't personally own, but I believe a lot of people on /r/bettafish use this one and like it.

Glass Canopy $20 Not necessary, but I think they look nicer than a bulky plastic hood. I do suggest some kind of covering for your tank since bettas are known to jump. It could be something as simple as a big sheet of plastic canvas cut to fit, which is a couple dollars.


So technically the above gear, assuming you buy the most inexpensive filter option, comes to $41 pretax. A little over the $39.99 all in one kit you originally wanted, but you are getting twice the gallonage, and also higher-quality gear--glass tank instead of plastic, and a semi-decent filter. And again, you could go a lot cheaper on the lid if you were so inclined and either save your money or put it towards a more expensive filter.

You'll also need a heater for a betta. I think a lot of fishkeepers have their favourite brands for this kind of thing, Hydor Theo is mine, self-regulating glass heaters are way better than the plastic pad kind without regulators because it turns itself on and off automatically as needed. Also, I would recommend ALWAYS getting a heater that can be adjusted to whatever temperature you need. Treating certain illnesses require you to turn up or down the temperature so that's an invaluable feature IMO. Also the knob on this model (unlike a lot of brands I've tried) is really easy to turn so that's kind of a bonus when your hands are all wet.

Whatever you do, I HIGHLY suggest real plants. Java fern, Anubias, and marimo balls are all great. No need for special substrate as the rhizomes need to be exposed to light. Just tie down to weights, decorations, or rocks. (You can use stones from outside, but make sure they are smooth, and boil them to kill any bacteria. Do not use soap or bleach to clean the rock, as the residue will kill your fish.)

5 gallon tank is recommended here. I will say I’ve kept bettas in 2.5s before and they’ve done great, but my boy seems much happier and active in the 5.5 I got him. (Only $13 at petco and the aquarium hood I got for it was $31 when I bought it, but the price went up. They rarely sell this hood in stores.) you could also go for a 5gallon tank starter kit which is usually cheaper. I just didn’t buy a kit because I already had a filter and such.

A heater/thermometer and filter are needed. Preset heaters are ok, but if you can afford an adjustable heater, that is better. Most preset heaters aren’t the best, but they’ll still keep the water from getting cold. For filters, I recommend a sponge filter that will double as a bubbler. This will clean AND aerate the water, as well as break up the film that will form at the top of the water. It will help your betta breathe much better. I have this filter and this air pump from amazon and am please with them. :)

Water treatment: you will need water conditioner to dechlorinate your tap water and make it safe for your fish. I use API Stress Coat+ and it does well. I also use Indian almond leaf “tea” to manage the pH. more info here You’ll also want something to test your water with. Many people recommend the api master test kit. I use tetra’s 6in1 test strips and they have served me well. Only thing is you want to check them before purchasing, so don’t buy online. Occasionally the nitrate pad comes brown and is faulty. Only reason I use those instead of the master test kit is I can’t find one that will test for all six things. They normally only test for four.

it's not going to be the cheapest option, but getting yourself a glass versa top and an LED fixture to set on top of it is your best bet. Basically any pet store will carry the glass tops, Id be wary of ordering a sheet of glass online.

I would personally recommend the finnex planted + or the finnex stingray, depending on what type of plants you hope to grow (the stingray will be ok for low/med light plants, you'll want the planted + for any high light plants.) Give it a few weeks and look for black friday deals on amazon :) The planted + in 20" runs about $75, the stingray about $50 without sale prices.

Alternately, you could just look for a balast that will support fluorescent bulbs, but they need to be replaced every 6-8 mos as they stop putting out the correct spectrum of light.


For a really quick, cheap supplement, you could look into getting something like this and just glueing or VHB taping it inside your current hood. It's the correct spectrum for plant growth, surprisingly bright, and very cheap. The cord is super short though, which is a pain. I use these to supplement light in my two 15g low light column tanks, and its made a pretty noticeable improvement.

OK so... Firstly, I wanna say, SIP to the sweet boi who has gone to the great beyond.

My Favorite option of the 3 TopFin Tanks you mentioned:

HANDS DOWN NO CONTEST - TopFin 5.5g Essentials Kit - Bigger volume of water over the 5g minimum recommended, but tank has a reasonable footprint on size at 16 in. L x 9 in. W x 11 in. H.

PLUS it is the better value of all 3 tanks (Essentials 5.5g $40 not on sale, $20-35 on sale). The other two cost a bit more (Retreat $50, not on sale) or even a lot more (Engage $60, not on sale).

The included HoB Filter can be easily and cheaply modified too (although I chose not to use them as I personally prefer using sponge filters): https://i.imgur.com/QYNiVEV.mp4

With the following supplies:

• https://www.amazon.com/Aqua-Clear-A1370A1-Aquaclear-20-Gallon/dp/B0006JLO5K/
  
• https://www.amazon.com/Aqua-Flo-Aquarium-Filter-Media-Thick/dp/B01J5MV86S/
  
• https://www.amazon.com/3IN1-BIO-SPONGE-Biochemical-Sponge-QUACLEAR/dp/B00VPL0V0W
  
• Intake Sponge - https://www.aquariumcoop.com/collections/intake-sponges something like this, that slides over the intake tube, not sure what size as I don't use the included HoB though.
  
  OR if you're like me and don't like HoB filters, this tank kit easily lets you add in just about any other filter, or even more than one filter if you want (you may have to mod the lid's big gap normally meant for the HoB filter to block, but it's easy - I cut up some cross-stitching plastic grid and glued it in place to block the large gap so betta can't jump out from there).
  
  (OR there are glass lids for the 5.5g tanks with vinyl parts that can be cut to fit your custom setup). https://www.amazon.com/All-Glass-Aquarium-AAG29016-16-Inch/dp/B001HYB8KY
  
  ​
  
  JUST look how pretty it can be (Disclaimer: Live plants are always better, but I have my personal reasons for staying with mostly silk plants for now)! https://i.imgur.com/x7VLj4l.mp4 AND https://i.imgur.com/ty9t3RJ.mp4
  
  ​
  
  The other two tank options have BUILT-IN filters which I DO NOT LIKE... Why?
  
  Well FIRST and FOREMOST - they are BUILT-IN to the tank, meaning they 100% take away ALL that space from the rest of the tank = LESS space for your fish to enjoy. The other issue with those tanks is... the flow from the pumps can still be quite strong - mods would include poking holes in the plastic tubing to reduce the water pressure by making it leaky and thus reduce flow, but then it can get pretty stagnant (I've once had a similar tank with built-in filtration compartment, and I really ended up hating it). Then the additional MEGA-HEADACHE if the filter pump breaks, it's often difficult to find a proper replacement water pump that still fits into the proprietary built-in filtration compartment (and doesn't have some crazy outflow) - most likely you will be forced to just replace the entire tank altogether. You could TRY to fit some other alternative filter into such a tank outside of the compartment, but that takes away EVEN MORE space from the fish living in the tank. The Engage's "HydroChange technology" feature is cool at first glance, but in reality it's really just a gimmick, and maybe only useful as a quick partial water change - maybe good for in between regular weekly water changes, but won't work as well as actually siphoning out debris from the bottom of the tank like you should with an actual gravel vacuum. These are all factors I took into consideration when I myself was making a choice of tank upgrade from previous 3.5g TopFin Enchant starter tanks.
  
  To sum it up, I would say the TopFin Essentials 5.5g kit is your best value, and most customizable tank option for a betta tank.
  
  Please do FISHLESS cycling of the new tank, whichever tank you end up choosing. http://injaf.org/articles-guides/beginners-guides/the-nitrogen-cycle-and-the-fishless-cycle-getting-your-aquarium-ready-for-fish/

Hello! The tetra 3 gal is the best choice imo of the 3. If you don't want to go all out, then this hood and basic tank. Petsmart has small 5 lb bags of white or black sand if you don't want to do gravel and depending on what all you will have in you tank, I've found sand to be pretty easy to deal with when cleaning tanks. I'm a big fan of Hydor heaters and I've heard a lot of good reviews on Eheim too.

In all honesty, if you are able to go just a little bit bigger, I'd suggest a Fluval Spec V. I have 3 tanks and 2 of them are the Spec V's. They're sleek, have a nice pump that has not only adjustable flow, but has a directional nozzle, you can fit a Hydor heater next to the outtake tubing, and already has a light. If you get that with a heater, you can take a small bag of sand, the Sponge Bob pineapple home, some colorful silk plants, and a moss ball or two you'd be all set as a beginner and not have it take up much more room. If you do get a snail, perhaps your son would name it Gary? (the snail in Spongebob? haha not necessary but it is possible to have a vacuum to eat any leftovers the betta doesn't eat.)

Just remember that if you move a fish tank, you'll want to drain out some of the water to make moving easier as well as safer. I take it this will be pretty sudden so a fishless cycling won't really be a thing so please make sure to have betta water conditioner.

Good luck!

Okay say you want to start with a 10g due to space constraints. Thats okay, its a nice starter size. Easy to work with space, easy water changes, just not a lot of livestock but thats okay we can concentrate on plants.


10g: $14

Stand: ..depending on what kind you get, used, material, etc etc lets say $25-40

Glass top: maybe $20 or so http://www.amazon.com/All-Glass-Aquarium-AAG29020-20-Inch/dp/B0002AS7ZI/ref=sr_1_1?ie=UTF8&qid=1398525732&sr=8-1&keywords=glass+top

Light: also depends on what kind you get. Low easy set up? A light might just be $20. Something higher power? $50+~~~? I have a fugeray on my 10g http://www.amazon.com/Finnex-FugeRay-Aquarium-Moonlights-12-Inch/dp/B007URQQMC



Substrate: I'd keep it basic and stick with ecocomplete, fluorite, or whatever popular commercial ones are out there. $20 a bag.

Root tabs, fertilizer, CO2 supplement: Dont need it, helpful, $15-20+

Driftwood: You can get nice cheap ones like malaysian and mopani starting at $4-10... depending on size. Then theres fancier ones like manzanita, grapewood, etc that can be $20 a piece.


Heater: $20

Thermometer: $2-4

Liquid Test kit: for checking water parameters, highly recommended. $30

Tetra safestart or bottle of ammonia: To either jumpstart cycle or doing a fishless cycle $4-10

Filter: Really depends on what you are planning to get too. If you are doing simple, low amount of fish, like 5-8 little ones or shrimp.. no problem with getting a basic 10g aqueon or tetra filter.. $16-20 If you know you'll be putting in a lil bit more or want a bit more customization, the aquaclears are very very nice $20-30. For SUPER cleaning, a canister filter (theres many different brands) but the price does go up and it needs to be placed under the tank- like in the tank stand. $50-100. Getting filters rated for higher than your tank is a good idea, but something TOO high will cause crazy water flow issues. I had a 20g with a aquaclear filter for a 110g tank and it worked fine for me. But the water coming out of the filter might have blown stem plants all crazy if I had plants in there.




Plants: $1-?? depending on quantity, quality, rarity. I often buy from local sellers or hobbyists at theplantedtank forums.
Fish: ??? up to you

CO2 setup: Optional. Can be DIY yeast set up which costs a few bucks to hundreds of dollars for fancy equipment.

Wisteria loves to float. I've let it go like that for weeks and it's happy to just chill and make roots until I decide it's time to plant it.

I would recommend a top like this. I believe 36' is the standard for 20L. Pair it up with a light like this and you're good to go. Big investment but I absolutely love mine. If you're buying a new hood with light included, make sure the light is actually better than what you currently have. I feel like the vast majority of them are pretty dim, though the bulb can be swapped of course.

Otocinclus Catfish are small algae eating armored catfish that get about 2 inches long. They are shy, peaceful fish that eat algae. You can compare them to a dwarf pleco pretty much.
There is no need to QT plants and I'm not sure what you mean by which way the stems will grow out from. The only thing I can think of is that you're asking which way you should plant the seeds? Plants always grow towards the light, so you should have no problems there. I would recommend starting with plants that are already grown though. This way, even if you have low lighting, they'll be a decent size and you won't have to wait ages for them to grow.

I see you have new questions! Here we go:

• Aqueon Versa top lids will fit pretty much any tank. If you get a standard 10g you can order this and it will work fine for you. As for lighting, I use this. It grows my plants ridiculously fast and also has blue lights for nighttime use. It as adjustable "feet" so it's guaranteed to fit your aquarium.
  
• I would suggest a Aquaclear 20 or Marineland Filter for your tank. Aquaclear is pretty much the best thing ever. If you're worried about flow, there is a slide option on the top that will reduce the amount of water coming out. You can set it to whatever you like.
  
• Tannins are a compound found in plants, this will not hurt your fish at all. However, if not removed, the tannins will color your water yellow. I haven't seen pre-soaked driftwood in petsmart/petco. You can try ordering it online and simply boiling it or soaking for a few weeks to get the tannins out.
  
• I make bullet points by clicking the bullets option above the comment box, this may be a feature of reddit RES though. You can make bullets simply by typing * and putting a space behind it.

I do like the "night light" feature on that hood, however I did intend on having live plants. Are there any plants that will survive/thrive in the light provided by a hood like that? I'm not opposed to fake plants I suppose, but was surprised to hear that the LED lighting on this wouldn't be enough for live plants. One reviewer says "I think it would work with plants, but you might need one more light kit. This would give you better light for the whole tank"... but how would you even add more lights onto a hood like that?

I guess I'm just a bit confused looking at all these lights online. I'm guessing if I don't get a hood, my other choice would be a strip light and some sort of glass aquarium top like this? -- do you think that and a stronger(?) LED light would be sufficient for live plants? I just don't want to spend too much on lighting for such a small unit.

edit: Couldn't find any T5s in 20" so now I'm considering getting a modular Aqueon light and two additional LED strips

Here are great products for the 2.5 gallon aquarium.
Aquatop Caf 10 sponge filter: https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=Aquatop+Caf+10+sponge+filter

Cobalt Aquatics 5 watt heater (depending upon how cold the office gets in the different seasons): https://www.amazon.com/Cobalt-Aquatics-Mini-Therm-Heater-watt/dp/B0090I7RC2/ref=sr_ph_1?ie=UTF8&qid=1526348775&sr=sr-1&keywords=cobalt+aquatics+mini-therm+heater%2C+5+watt

Aqueon Versa Top lid for 2.5 gal (this one is the wrong size but look for the 2.5 gal size for your tank: https://www.amazon.com/Aqueon-Aquarium-AAG29020-Versa-20-Inch/dp/B0002AS7ZI/ref=sr_1_fkmr1_1?s=pet-supplies&ie=UTF8&qid=1526348866&sr=1-1-fkmr1&keywords=aqueon+versa+top+lid+for+2.5+gal+fish+tank ) You will need this lid so that your Betta doesn't jump out accidentally and it needs that water to be to the top for it's maximum 2.5 gallons.

I have 3 tanks that size with lids. You will have to find a LFS that has one. Good luck!

$64 is pushing my budget, since also I have a 10 gallon that might need lights. (no plants in there yet) Got any other recommendations? I might need to get a job just to take care of my tanks XD. If there are cheaper diy solutions (possibly led?), I could probably do that, I have a soldering iron. edit: What about this? and this?

Aquarium light
Aquarium heater
Aquarium filter
Aquarium lid
Water Conditioner
Water test kit
And then you can get the aquarium (10g) at Petco
I strongly recommend live plants: Java ferns, anubius, Marimo Moss Balls, bacopa, cryptocoryne, Valisnaria, hygrophila, easy low light plants. Malaysian, Spider (not sharp), Mopani, and manzanita are all good types of drift wood for a betta aquariums

Indeed I do!

It doesn't photograph all that well, but here is someone's video of it. It's pretty cool looking.

I know but compared to what I had (this was for one set) before I'm looking to spend something like this

I'm really picky ha

I am fairly new to this so my friend who also posts here, her tank http://i.imgur.com/e2A1RBO.jpg , has been pmuch holding my hand the entire way. My plants were all selected for a low light setting since I am doing this on a small budget but this is the lighting I am currently using http://amzn.com/B00474BN1K. My lighting schedule is to have the led's on 10 hours a day with natural light coming in through the window as well and then swapping my led's to the "night time" setting when I go to bed. I will be adding a few guppies to my tank this week to cycle it in preparation for the Crowntail or Halfmoon Betta I am getting...haven't made my mind up yet.

I really like the way that glass hoods look. I think you can usually get them for a little cheaper at a petco/petsmart.

If you want to go super cheap look up diy cfl aquarium lighting. I have a Finnex planted + and love it, but they are a little pricy.

You could try a cleaner that is a stronger acid than the vinegar is, or let it soak in vinegar.

If you end up needing to get a new one, I know that even though the picture does not show it, the 72 gal glass top sold on amazon is in two pieces.

H2Pro 30" Glass Canopy for 20... https://www.amazon.com/dp/B01F5ZXLXM?ref=ppx_pop_mob_ap_share
This is the lid that I have for my 20 long and I love it!

cover it’s glass but it’s a pretty cover

i bought this for my 29 gallon tall and my plants took off right after. i would highly recommend it. make sure to get the sun light and the plant light.

Well, that's reassuring, I appreciate the help. This is the hood I use. I usually leave it on for around 8-12 hours every day. All kinds of the leaves and stems have fallen off and have been getting stuck at my filter and floating on top of the water. Another issue that might be the problem is I left the weighted band on the plants, should I take that off?

This is the light/hood I have https://www.amazon.com/Tetra-LED-Aquarium-Hood-16/dp/B00BLRNAI0 Is that a decent one?

I'd just buy everything separately, because aquarium kits often lack in the quality department unless you get a really nice one - like the fluval tanks. Really depends on what tank you get though.

I have this lid and this light on my 10g.

That's pretty much what acrylic and plexiglass costs.

How many gallons is your tank? A 20-gallon hood costs about $50 on Amazon.

http://www.amazon.com/Fluorescent-Black-Hexagon-Gallon-Hood/dp/B0002AS5VY

I think that's an aqueon 45 gallon. They are usually sold in a set so they are a bit less common. Searching for rounded dimensions usually works a bit better than precise measurements. They always round them in product names and have detailed measurements in the description.

Aqueon AAG29036 Aquarium Versa Top, 36 x 12-Inch https://www.amazon.com/dp/B0002AS80C/ref=cm_sw_r_cp_apa_i_f9lGDbMV7V55E

Just buy a separate lid. Versa are really common. They have them at my local shop (I got a 5.5g, 10g, and 30g lid from there) and I've had success ordering one for a 2.5g before.

For a standard 20" long 10 gallon: https://www.amazon.com/Aqueon-Aquarium-AAG29020-Versa-20-Inch/dp/B0002AS7ZI

Here ya go.

40 bucks for the filter/heater/Hood.


Also make sure you get some water conditioner.

Oh and if you are doing plants you should get some fluorescent bulbs.

This one and I will look into the mosses. Thanks for the advice!

Alright, I'm also tempted to go with 2 of these to save money, but I'm starting to realize that they will not be able to accommodate bulbs with enough power to produce sufficient PAR.

Fluorescent Hood

Would these hoods and 2, 18" t5 or t8 bulbs be enough for a 55 gallon?

The glass tops are narrower than the tank, because people use a plastic backstrip that can be cut to accommodate filters, etc.

If you can't find a glass top to fit, go to a glass shop and have 2 panes cut for you. The glass shop can supply you with a handle. You can buy the hinges and backstrips online or from a LFS.

it is a long. Do you think this would be fine for my aqueon 20g long?

you could just buy one
https://www.amazon.com/Perfecto-Manufacturing-Marineland-Fluorescent-Specialty/dp/B007QH5IMA

You might even be able to cut that yourself if you want. Just get a piece of glass bigger than what you need it to be and do some cutting :). (do the pentagon-edge last I guess)

Or a piece of plastic.

you could also try geting one second hand.

You can purchase a glass flip lid that only leaves a small portion of the surface open in the back for gas exchange and filters that actually does a really good job with blocking a ton of evaporation.

Hmm most glass lids ive seen and own have a plastic piece along the back that you can cut to accommodate filters and such. Like these https://www.amazon.com/gp/aw/d/B0002AS7ZI/ref=mp_s_a_1_1?ie=UTF8&qid=1523235399&sr=8-1&keywords=aquarium+glass+lid

Maybe this - in the question-answer part, someone says it fits a 125.

​

EDIT: And here's the extender to get it closer to the 17.

I got a 20 L and this hood -> http://smile.amazon.com/Marineland-Light-Hood-24-Inch-12-Inch/dp/B00474A3DY/

Here is the mobile version of your link

So far I have found these, but I don't know what to think. Any thoughts?

http://www.amazon.com/All-Glass-Aquarium-AAG29030-30-Inch/dp/B0002AS802/ref=cm_cd_ql_qh_dp_t

http://www.amazon.com/All-Glass-Aquarium-AAG21230-Fluorescent/dp/B0002AS5BO/ref=cm_cd_ql_qh_dp_t

https://www.amazon.com/dp/B00474FPZU/ref=asc_df_B00474FPZU5377817/?tag=hyprod-20&creative=394997&creativeASIN=B00474FPZU&linkCode=df0&hvadid=167154348866&hvpos=1o1&hvnetw=g&hvrand=14955736999884686714&hvpone=&hvptwo=&hvqmt=&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=9026334&hvtargid=pla-305608341730

This is the one I have. https://www.amazon.com/Marineland-Light-Hood-30-Inch-12-Inch/dp/B00474BN1K?th=1&psc=1

What should I have had purchased?

A glass top should leave enough room for the filter. You should be able to get one at just about any pet store.

I meant the back of the lid, my bad lol. Here's what it is

I have this one for my 10 gallon. Has plastic section on the back to cut places for filter, heater, etc. to go:

https://www.amazon.com/Deep-Blue-Professional-ADB32010-Standard/dp/B0042FRN8G/ref=sr_1_1

Think I am going with this method. I have 2 pieces of glass that were a part of an old tank I should be able to make it work if i cut it properly.

So this is what I've found from looking into lids since I'm not a fan of hoods:

I have a plastic lid on my 7.5 gallon and the moisture causes it to bow down in the middle. I just flip it over every week to keep it to a minimum. I think this would be more pronounced on a 20 gallon, though it would obviously depend on the thickness and type.

You could get a glass lid (similar to this). It has a hinge and the back 2in or so are plastic so you can cut out holes for filters/cords and such, or you could remove that part altogether. On mine, the back 2in are left empty for the same reasons, and I still have suicidal fish :(

I've seen people use egg crate and plastic light diffuser panels that they've trimmed down to size. The latter is nice because it keeps condensation down (because of the little spikes) but creates a lot of issues with lighting (since it diffuses it...)

https://www.amazon.com/MarineLand-Light-Hood-Aquariums-Night/dp/B00474BN1K/ref=sr_1_4?ie=UTF8&qid=1549404923&sr=8-4&keywords=aquarium+lid

These cheap ones that have really weak lights in them that can't support plants.

I searched for plastic ones on amazon then google. Not seeing a thing.