I bought a new Diamond Goby today to do some sand sifting. We acclimated him over a period of one hour by letting his bag he came in float in my tank, and adding water from my tank a little at a time. He hasn't spent any time on the bottom of the tank and has spent most of his time in the water getting pushed around by the currents of my powerheads. He swims up to the top and swims along the top, with his body in a vertical position, until he hits the powerhead, then he follows the current and starts all over again. Are these fish just really bad open water swimmers. Whenever he's moving around, his body is in a full vertical position. Water parameters are as follows:
Alkalinity: 12 dkH
Water Temp: 78°
I noticed that one of the fins on his belly isn't moving like the other one. Would this cause him to swim the way he does. I've noticed that when he gets tired of swimming around, he will lay on the sand bed on his side and not move, then he gets up and starts swimming at the top again. Listed below are tank specs.
90 gallon tank.
115 pounds live rock.
2 BioWheel 280 filters.
2 Koralia 750 gph
(Not sure on the light exactly off the top of my head but it is listed on my page)