Fish Madness

[Jv777j]

I have a 15 gallon tank with 4 two-three inch tiger barbs, 4 platys, 2 balloon mollys, and a common pleco that I'll rehome because he is getting really big. My tiger barbs never bother the other fish and I know that tiger barbs are semi aggressive. So my question is will they ever be aggressive? Should I be worried that they would become killer fish later on?

 

[Jammiedodger]

They won't just turn into 'killer fish' overnight, in fact they likely won't at all with the right tankmates... just watch out for fin nipping in such a small group as ideally tigers need 85 litres+ to sustain a group without any problems.

 

[KittyKat]

I think it is likely that they will become nippier over time unless you keep more of them, but in a tank that size, I would say there's not enough room for a "safe" group (which I would say is 10-15+). I also think that they should have at least a 2.5-3 ft tank.

Also, they are a schooling fish, so I strongly recommend that they are kept in a larger group (6+) anyway.

 

[Jv777j]

They usually just stay together in their little group. They just ignore their surroundings. Even when one of my fish was pregnant they just stayed away... Well atleast until they were born. Luckily I saved 30 fry.

 

[KittyKat]

They usually just stay together in their little group. They just ignore their surroundings.

The point I'm trying to make is that they will probably be more comfortable in a bigger group and will interact with each other and their environment more. They stay together because they are shoaling (and neons are schooling) species; this means that in the wild, they live in groups of around a few hundred to a tens of thousands (depending on the species), so they generally act like they are more secure when kept in groups that are too large for them to (as close as fish come to it) "count" individuals. It's a bit like going from "1 fish", "2 fish", "3 fish", … to "few fish" and then to "many fish". In my experience, most species go from "x fish" to "few fish" at the 6 fish count, and from "few fish" to "many fish" around 10-15 fish.

With tiger barbs, the nippyness increases around sexual maturity which is why having more targets of the opposite sex to show off to decreases the amount of time they have for spending on nipping other fish.