I have a 20 gallon long currently stocked with a single male koi Betta, a single female(?) Copella sp., and seven Pristella tetras. I'm interested in adding a few more fish, and my LFS has a single Orinoco dwarf pike (Crenicichla sp.) and some Kuhli loaches. I was thinking of adding one or the other.
I'd prefer the dwarf pike, but I'm not sure the 20 long is suitable. I've been reading around some with mixed opinions. First off, the dwarf pikes can be quite territorial, especially Crenicichla compressiceps, and the recommend tank sizes are quite large for a pretty small fish (55 gal for a 3-4 inch fish) simply because they are extremely intolerant of each other. From what I've read the Orinoco dwarf pike is more similar to Crenicichla regani, a much less aggressive fish. In addition, I would only be keeping one so I wouldn't have to worry about intra-species aggression. However, I would still worry about inter-species aggression. The Orinoco dwarf pike will probably reach ~4inches which is pretty large for a 20 long. However, they are really thin-bodied fish. Kuhli loaches themselves reach 3-5 inches and it's pretty well established that they would be fine in the 20 gallon. On the other hand, the Kuhli loaches would have no problem in the 20 long and they would add some activity to the bottom of the tank. If I get the Kuhli's I would need to get a small group which increases the bioload more than I like. Also, I am somewhat worried that the Kuhli's would just hide all the time.
What do you think? Should I go with the dwarf pike or the Kuhli loaches?
P.S. my LFS also has Rosy loaches, but I'm not that sold on them. Should I consider them?
I'd prefer the dwarf pike, but I'm not sure the 20 long is suitable. I've been reading around some with mixed opinions. First off, the dwarf pikes can be quite territorial, especially Crenicichla compressiceps, and the recommend tank sizes are quite large for a pretty small fish (55 gal for a 3-4 inch fish) simply because they are extremely intolerant of each other. From what I've read the Orinoco dwarf pike is more similar to Crenicichla regani, a much less aggressive fish. In addition, I would only be keeping one so I wouldn't have to worry about intra-species aggression. However, I would still worry about inter-species aggression. The Orinoco dwarf pike will probably reach ~4inches which is pretty large for a 20 long. However, they are really thin-bodied fish. Kuhli loaches themselves reach 3-5 inches and it's pretty well established that they would be fine in the 20 gallon. On the other hand, the Kuhli loaches would have no problem in the 20 long and they would add some activity to the bottom of the tank. If I get the Kuhli's I would need to get a small group which increases the bioload more than I like. Also, I am somewhat worried that the Kuhli's would just hide all the time.
What do you think? Should I go with the dwarf pike or the Kuhli loaches?
P.S. my LFS also has Rosy loaches, but I'm not that sold on them. Should I consider them?