Stocking question

[caseyt]

Last night, my roommate inquired about adding a red tailed shark to one of our tanks. Given the current inhabitants (who seem to be pretty happy) is this an option?

20g Planted

4 neon tetras
4 zebra danios
3 lamp eye tetras
3 otocinclus
2 african dwarf frogs
1 male betta

10g Artificial plants

3 albino corys
2 black mollies (1 juvenile)
1 male cherry barb
1 male betta (these two get along rather well, btw)

I know the RTS would need to be in the 20g at the very least, which I believe is currently at full capacity or very close to it. I *suppose* I could move the lamp eyes to the 10g to make room for the shark, but I would also probably want to add a neon or two to the 20 to increase the size of the school in case the shark is a problem to them. I'm also concerned that adding the lamp eyes to the 10g may be pushing the capacity a bit as well.

Another note, is it a fair assumption that the ADFs require as much tank space as a fish of proportionate size in the 20? Should they be given more space?

Thanks for your input.

 

[OrionGirl]

I wouldn't put a redtail in anything smaller than a 30. While they are not usually aggressive to dissimilar fish, they can be nasty brutes. Providing them with several caves can help, but as they grow, may not be enough.

Rainbow sharks tend to be a bit more mellow, though they too will harrass fish of a similar shape, and get to about 5-6 inches. Your 20 probably could support another fish, depending on your maintenance routine. You don't seem to have any fish that would compete for the caves.

I'm not sure on the ADF. I don't think they are territorial, but they may produce slightly more waste than a similar sized fish--think of them more like a cory than a tetra, I think. I know the african clawed frogs can be messy--much more so than a similar volume of thin bodied fish.