thoughts on why some fish seem to like the bubbles???

[Magnum Man]

so... increased water movement??? my panda garas and several other hillstream's seem to prefer the bubbles to the flow created by the hang on tank filters... maybe the bio film is heavier in those areas, either from water movement or a static charge deposit from the air??? is the oxygen level higher there??? I would expect the water circulation from the filters would equalize that through out the tank, in short order???
... maybe just for fun or mental stimulation???
what say you???

 

[GaryE]

Most people run bubbles at the back of the tank, so the fish can cling to the glass to feel the flow. A lot of fish have adaptations to fast water - Ancistrus, Otocinclus, hillstream loaches - hang on for dear life mouth parts are pretty common.

So the fish is attracted to the habitat it's adapted for. When I run powerheads so they hit the glass and flow along the back wall, the wall is popular.

HOBs generally oblige the fish to be midwater, and suction mouth parts are useless there. I have some tetras that never go to the calmer regions of the tank, as well as some that avoid the flow. The boulder clinging species, which are often feeders on biofilm, can use that current, and it rarely feeds the growth of biofilm.

 

[Magnum Man]

I find smaller Hillstreams regularly inside the hang on back filters, on that tank... they climb the output waterfall, so that supports the water movement idea... in my bitterling tank, I have a large block air stone, in one front corner, and there is at least one of the three little baby panda gara's on the glass, day and night in that corner... most often the side glass that faces the hall light, that is one more often than the room light, occasionally all 3 garas, most often 2 of them... ( there is a similar air stone in the opposite corner, being back side and in the darkest corner of the room, I can't view there, but would guess if they aren't above one air stone, they are over the other...