Are air pumps or stones necessary for a healthy 20 gal tank?

Herky

So air pumps + planted tanks = bad to make a long story short?

Byron

Assuming you mean air stones or similar devices that produce bubbles in a planted aquarium, yes, not good. You would be fighting against the plants.

Herky

yeah, that's what I meant...good stuff to know. speaking of plants...I checked out petco and petsmart's plant section yesterday...wow what a load of crap they sell there. All of their plants were like 80% rotten. Didn't buy any.

SinCrisis

watch out, some plants at petco and petsmart are bog plants and will melt if left underwater for too long ~4-6 months. IF you are lucky though, sometimes you can find a new shipment and get nice plants

Tyyrlym

The big chain's selection is iffy usually. The turnover on plants isn't as high as fish so often plants will be left in their holding tank far longer than the fish. Additionally I know most of the Petsmarts around me use a manner of filtration seemingly designed to drive off CO2. Finally, I would shy away from them anyways due to most of their plant tanks being snail infested.

I would not recommend replacing a mechanical filter with plants only. While most aquariums will benefit from the inclusion of plants they don't have the throughput of a mechanical filter. In order to let the plants and their accumulation of bacteria to fully take over filtering a tank you need a lot of plants and only a few fish.

SinCrisis

From my experienced, plants i get from petsmart or petco never have snails. Maybe its a store to store thing? My local petco and petsmart have a couple fo fish in their plant tanks, petco has a Koi and petsmart has 2 clown loaches in the plant tanks. However, i did get snails from a lfs near me and all the lfs' near me have snail infested plant tanks. Either way, inspect your plants before you plant them.

If you do get plants however, it will be wise to remove the carbon.

Tyyrlym

Yes, if you get plants don't run carbon. Any ferts or liquid CO2 additives you use will be removed by the carbon. Either depriving your plants of nutrients or accelerating your carbon's deactivation, however you want to look at it.

The loaches in your Petco's tanks are likely taking care of the snails. The stores near me are absolutely overrun with the things. I think they gave up trying to prevent it and now just sell snails out of the plant tanks. Personally I'd just run some copper in that filter system and be done with it.