20G Community Tank

[kenkat]

I have gotten a 20G tank, I was looking to get 5/6 Glofish Tetras or Danios, and 5/6 catfish coryadoras, and like 5 or 6 cherry shrimp, a couple nerite snails. Is this okay in terms of stocking? If so, I was wondering how much more I can get. I would like to have another type of fish if possible.

 

[HoldenOn]

Cories and Tetras do work together but they are schooling fish and need to be kept in groups of 6 or more.

 

[kenkat]

would 6 of the cories and 6 tetras be fine for a 20g?

 

[mbsqw1d]

Yeh if its a long aquarium as opposed to a tall one. These fish do well soft water too, would you happen to know if you have soft or hard water?

 

[Byron]

I would not recommend danios in a 20g tank. Danios are active swimming fish, and they need more space (tank length is the issue here).

Cories can manage in a 20g, and a group of 8-9 would be best. They are more settled the more there are, which means healthier fish.

The Glofish Tetra, if this is a "tetra" and not a "danio" glofish, could manage in a group of 7-8. Personally I would look at smaller fish, because you can have more of them (more fish and more species) and this makes the aquarium more interesting. A 20g is not all that much space to the fish. Knowing your water parameters will help us suggest suitable fish. I see you are in NYC (New York City presumably) and your water there is (or was) quite soft. Can you post the GH and pH of your tap water just to be certain? You should be able to get this from the water authority, check their website.

 

[kenkat]

Not sure but I can check. Is there space for anything besides the 5 or 6 tetras and corydoras, for the 20g or is that pushing it?

 

[kenkat]

GH is 8 and ph is about 7.2 from what ive read

 

[Byron]

Not sure but I can check. Is there space for anything besides the 5 or 6 tetras and corydoras, for the 20g or is that pushing it?

You want more than five or six of a shoaling species, no matter the tank, as this will actually help overall. But the 7-8 tetras and the 8-9 cories will be it. But if you do have soft water, you have a wide range of options in smaller-sized fish.

GH 8 is soft water. If you are set on Glofish, fine, though to be honest there is a view in this hobby that these fish should not be acquired. Genetically-engineered fish is not a sensible procedure these days. There are many natural species that will thrive in your tank.

 

[kenkat]

Ok if i were to get 8 corries, and not the glofish, what are some options I could go with if i wanted 1 or 2 more species to go along with the corries

 

[CassCats]

Id go:

6-8 smaller tetra or rasbora species
6-9 corydoras of your choice
1 bolivian ram or 3 honey gourami

 

[kenkat]

Sorry for all of the questions, had another question. Instead of having a few species of schooling fish, if I was to have 2 or 3 bigger fish of the same species or different species that aren't schooling, would it be possible for 20 gallons and if so, what species?

 

[Byron]

Sorry for all of the questions, had another question. Instead of having a few species of schooling fish, if I was to have 2 or 3 bigger fish of the same species or different species that aren't schooling, would it be possible for 20 gallons and if so, what species?

Now this is difficult. Gourami and cichlids are non-shoaling fish (most of them, there are exceptions among the cichlids) but they also get too large for a 20g, with few exceptions.

 

[kenkat]

ok, so i will probably go with the community tank. one last thing, and this is probably the biggest question. so i had a tank before with 5 glofish tetras. before i got them, i had cycled them, or at least i was under the assumption i had. the nitrate levels went up and the nitrite and ammonia levels hit 0 and stayed there or close to it. but the tetras all died after a week. some suggested that maybe it was because i hadnt changed my filter cartridge or bag for about a month and a half and hadnt cleaned the filter enough. i thought there was enough beneficial bacteria in my tank. i was going to get a new filter bag and cartridge for the 20g tank and get a stronger filter too. should i restart the cycle in my new tank or can i transfer the decor, and be fine? if i have to redo the cycle, i should go with fishless right?

 

[CassCats]

Go fishless and start with plants

 

[Byron]

ok, so i will probably go with the community tank. one last thing, and this is probably the biggest question. so i had a tank before with 5 glofish tetras. before i got them, i had cycled them, or at least i was under the assumption i had. the nitrate levels went up and the nitrite and ammonia levels hit 0 and stayed there or close to it. but the tetras all died after a week. some suggested that maybe it was because i hadnt changed my filter cartridge or bag for about a month and a half and hadnt cleaned the filter enough. i thought there was enough beneficial bacteria in my tank. i was going to get a new filter bag and cartridge for the 20g tank and get a stronger filter too. should i restart the cycle in my new tank or can i transfer the decor, and be fine? if i have to redo the cycle, i should go with fishless right?

We don't have all the data on the previous problem, so moving to the present...for the type of fish in this tank you want minimal filtration/water movement. A simple internal dual spong filter connected to an air pump is one good option, and another is a small internal filter like the Aqueon Quiet Flow that is basically a sponge and motor which eliminates the need for an air pump. I use these now in my tanks, from 10g up to 40g.

On cycling...are you intending live plants? You should have floating plants at least with these fish as they prefer "shade," and the water quality benefits are immense. Moving decor and filter media from an existing healthy tank will transfer over bacteria, but once the floating plants are growing this becomes unnecessary.