What do I do?

[Anna94]

So I have a 20 gallon long with an AquaClear 50 and 40 gallon sponge filter filtering it. The inhabitants are:
5 cardinal tetras (I plan on adding one more)
2 Celebes rainbows (I might add one more, but not sure yet)
1 horseface loach (I was told one would do fine in my tank)
1 kribensis
3 lemon tetras (I plan on adding two more)
1 oto (I might add a few more, but not sure yet)

In my AquaClear is the sponge, poly-fil, and half Matrix and half of my old biomax. I will be taking out the rest of the biomax and adding more biomax in 2 weeks.

I do 40-50% weekly water changes and dose with Prime and Stability. My tank has been established for 2 years and I've had these fish for 4-5 months. Ph is 8.0, nitrites are 0, nitrates are consistent at 10-20, and ammonia is consistent at 0.25-0.50.

I understand I'm overstocked, but my lfs won't take some of my fish and none of my friends or family have fish so at this point I either kill them just to get rid of them (which is inhumane and I'm not a killer of any kind) or I keep them (which is my only option at this point). So since I have to keep them is there anyway I can get ammonia to 0 and keep it at 0? I tested my tap water and ammonia is 0.

 

[DutchMuch]

Do you have plants in the tank? I suggest adding simple plants (a lot of them) like anubias or amazon sword, to lower down that ammonia until you rehome your fish.

 

[Anna94]

Do you have plants in the tank? I suggest adding simple plants (a lot of them) like anubias or amazon sword, to lower down that ammonia until you rehome your fish.

Again, rehoming my fish isn't an option as nobody I know has fish, and I thought plants only lower nitrates not ammonia.

 

[DutchMuch]

Again, rehoming my fish isn't an option as nobody I know has fish, and I thought plants only lower nitrates not ammonia.

Ammonia as well

 

[DutchMuch]

Any clue on which plant absorbs the most amount of nitrate/ammonia? - The Planted Tank Forum