Whirligig beetle in my tank?

[reggie oaks]

I can' t believe this. Today, i went to my office to feed fish in my small tank (2.5 gal). While anchoring a plastic plant, I disturbed the gravel and noticed a black particle moving and being chased by one of my danios. What I thought was a carbon stone moving with the current, turned out to be an insect. About 4 mm long, it ressembles a whirligig beetle. I' m very intrigued by this. Know that some of them have a predatory larval stage, or at least have the potential for being predatory as adults too. Any ideas regarding 1-where did it come from and, 2- if my fish on danger?

[MLBfan]

I don't know what it is, but why do you have a danio in that small a tank? That's waaaay to small.

[Reefled]

wow , so strange....pic ?

[ElizabethJKR]

+1 to MLB
Danios need to be in groups and in larger tanks.

[reggie oaks]

My mistake. It wasn' t wise on my part to put a danio in my office' s SMALL tank.
Sorry, no picture for now. [I WILL try to post one but I haven' t figure out yet how to post pics.] I didn' t either bother, since my camera was too far. What I did was to get a pippette and small petri dish to aspirate the insect. But since I was aldo dealing with work at the office, the insect was gone by the time I was able to gather some time for the operation.

Apparently it was buried in the gravel. IF i AM CORRECT (which I don' t know for sure) and it is a whirliwig beetle, they are mosty scavenger and forage algae, live on copepods and other microinvertebrates (some are predarory too, but mostly on these other small creatures). They tend to depend mostly on debris and particulate matter as food source. If anyone has any further idea, then please feel free to comment and let me know: " Mi casa es su casa" .

[reggie oaks]