miraloma

I just bought 3 long finned danios for my 10G tank that has 2 platys and 2 guppies. One danio just hangs up at the water surface, much like a betta. One chases the last one (with much shorter fins so I'm wondering if it's a regular danio rather than a long finned) relentlessly. The aggressive danio occasionally goes after my guppies as well. It seems to leave the platys alone for the most part. Which is the "typical" danio behavior - the betta like hanging out swimming gracefully, or the lightening speed chasing and darting around the tank?

Chief_waterchanger

Our danios are constantly swimming pretty fast. One problem is that you should have atleast 5-6 of them, it helps them feel safer and distributes any aggression amongst several members, making you less likely to have any one specific danio suffer too much. I think the danio would be happier in a larger tank with 5-6 or more of them. If you could get like a 20g with like 10 danio that'd be a nice tank to watch, but if you must keep them in the 10g I would make sure there is plenty of hiding places and a good bit of plant-life.

Dino taught me the trick to keeping skittish/shy fish and making them more visible and calm is to provide more places for them to disappear into. If they know they can get away into a hiding spot from almost any location in the tank rather quickly then they are more likely to come right out in the open to be viewed. Neato concept, and totally common sense, but kinda out there at the same time.

miraloma

I think the gracefully swimming one was actually dying. It was just hanging there, not bothering to move fins or anything. I was able to poke it with my finger and used a cup to scoop it up without any struggles from it. I went to the store and exchanged for a couple other ones. Now I have 4 danio's. Hopefully they'll play nice till I can add a couple more in my 10G.