Reddit mentions of biOrb Silk Plant Set Small Green & red (46099)

A few things I would change though, to improve the setup and make this 3.5g tank work out for the betta... (PLEASE READ and bear with me, I know it's long but you'll learn a lot I promise!)

1. That's WAYYY TOOO MUCH GRAVEL... jeez damn, that alone is taking at least 2+ inches of what could have been more water space + going to trap a TONNNN of debris with all that gravel... my recommendation would be to remove enough of it until the small finer gravel just barely reaches a bit above the level of black frame at the bottom of the tank, and then have the larger pebbles/rocks on top.
   
2. Fill the water till it's about 1 cm below the top black rim frame of the tank (that's how much I used to fill mine up to when I had the exact same TopFin 3.5g tanks).
   
3. I highly recommend these silk plants, both packs:https://www.amazon.com/gp/product/B003KGBJ06 AND https://www.amazon.com/gp/product/B003BG2TEAWith both packs, your tank will have nice and sufficient silk plant coverage. The taller plants towards the back, and the shorter ones to the front, those 4 will form a perfect mini jungle your betta will absolutely enjoy. You could try doing easy lowlight plants like Java Fern, but having had the same tank before, I think the rainbow LED light it comes with is far to dim to sustain most plants. Still you could try and see if java fern will be ok (they don't like their bulbous rhizomes buried though, so only bury the bit of the roots sticking out below the bulby-pill-shaped rhizomes).
   
4. Add 3-4 medium or large marimo moss balls (they look nice and they do eat up some of the toxins in the water) + Java moss [wrap some java moss around cables (heater cables)].
   
5. Add a 18-25w heater, preferably manually adjustable rather than preset, bettas absolutely DO need a heater, especially for winter months when its chilly. Their preferred comfy temperature needs to be kept at 78-80F. I do remember Petsmart has an 18w preset heater that's supposed to maintain 77 or 78F but I don't trust it, you can try it if you want but a manually adjustable heater is more accurate.
   
6. Ditch the included carbon cartridge (replacing that once per month is a money-grabbing gimmick by the pet store, because you should only ever need carbon filtration to remove medicine after a medicinal treatment of a sick betta, it's not really useful filtration otherwise). I recommend filling the big filter space with aquarium sponges cut down to size, towards the front of the filter where the outflow is + TopFin Quartz bioballs (you can buy a whole carton of them for a nice price) towards the back-half.
   
   1. https://www.amazon.com/3IN1-BIO-SPONGE-Biochemical-Sponge-QUACLEAR/dp/B00VPL0V0W <-- this pack includes fine, medium, and coarse sponges that you can layer inside the filter front (cut them down to size to fit if needed). Maintenance is the occasional gentle swish of the filter sponges in old tank water (NEVER RINSE IN STRAIGHT TAP WATER), about every two weeks or so (depending how gunked up they get).
      
   2. Add as much TopFin Quartz Bioballs (rinse them first in dechlorinated water) as fits in the space behind the filter sponges mentioned above.
      
      Other things you'll definitely need to have, and/or do:
      
      
7. API Freshwater Master Test Kit - You're definitely going to have to Fish-In cycle that 3.5g tank which means DAILY 25%-30% partial water changes to keep ammonia & nitrites low (you want those close to zero as possible to reduce poisoning of your betta during the process, so you need this test kit to be able to keep a careful watch on the ammonia and nitrite levels). ABSOLUTELY MUST HAVE, VERY IMPORTANT, liquid water parameters test kit. Three main things to check daily or every-other-day: Ammonia, Nitrite, and Nitrate. Not cycled will read 0 Ammonia, 0 Nitrite, 0 Nitrate. Cycling in progress will read some ammonia and/or some nitrite, but little or no nitrate. Fully Cycled will read 0 Ammonia, 0 Nitrite, and 5-10 ppm of Nitrate, then when nitrate reaches 15-20 ppm in a cycled tank a water change is necessary to reduce said nitrates.
   
8. Seachem Prime - best water dechlorinator out there, and perfect for Fish-In cycling because it helps temporarily neutralize smaller amounts of ammonia (under 1ppm).
   
9. Seachem Stability - beneficial bacteria blend which you'll need for establishing a nitrogen cycle.
   
10. Gravel Vacuum (mini size is good for 3.5g) - mandatory must-have item for tank maintenance, how else are you gonna siphon out the poo and food waste from the bottom of the tank? https://www.amazon.com/Aqueon-Siphon-Vacuum-Aquarium-Cleaner/dp/B004RK40VY/ should be perfect size for your tank.
    
11. 5g bucket (yes I know that's more than what your tank water volume is, but imagine having only a 3g bucket and you're trying to carry it to be dumped, or to carry it for a refill and it's going to be sloshing around as you walk, so a larger bucket will help reduce spills from some sloshing.)
    
12. NorthFin Betta Bits - one of the best quality betta pellets out there (little or no fillers, high quality ingredients, no nasty toxic preservatives) https://www.amazon.com/Northfin-Betta-Bits-Pellet-Package/dp/B01C1ARV3K/
    
    Also PLEASE watch out with the overfeeding, your betta in this video clip looks super bloated (his little tiny belly looks about ready to burst, he's so stuffed). You need to fast him for 3-4 days until his belly looks almost flat again, then you can try giving him some daphnia as a mild laxative to help him clear out any further blockage (not to mention a heater to warm the water to a stable 78-80F will help his metabolism so he can process the food properly).
    
    Here's a reference of photos to help you determine how much food his little belly needs: https://i.imgur.com/4RR2LZ9.jpg (feed slowly 1 piece at a time, watch his belly, and aim not to let it get too far past the 2nd from the top picture).
    
    Please read these articles to learn more how to give your boi the best quality of life: https://www.reddit.com/r/bettafish/wiki/index
    
    Only once your tank is fully cycled (0 ammonia, 0 nitrite, and 5-15ppm nitrAte) for a 3.5g tank, you will need to do one 30% partial water change (PWC) mid-week (Wednesday for example), and one 30% PWC at end of week (Sunday for example). Or if you won't be there over the weekend then do 1 PWC Tues. and 1 on Friday.
    
    Good luck!