HT tank runs hot...

[Adamant]

My fish are in week 2 of Cupramine treatment in the HT and the temperature of my HT stays about 27.8C during daytime dropping back to about 25.8C at night.

During the day, the heater doesn't fire at all - I've even unplugged it to check and it's doing nothing by day although in the middle of the night I've seen it light up.

I'm guessing it's my PH in the HT causing the heating but this is my sole source of gas exchange and water movement for the biological filter so it has to stay on.

Will a temp of just under 28C be OK? If so, am I better setting my heater to 27C to try and maintain that around the clock rather than the 25-26C it's currently dropping to overnight (with the possible risk that this will just give it a bigger head-start the next morning to maybe go even higher?)

Ideas?

Thanks,
Adam

[scooter31707]

what is the temp in the room during the time of the rise of the tank temp? Is it by a window? Do you have a any type of glass top on the tank?

[Sk8r]

[That's 82 F] ---Not too bad for the fish BUT higher temperature means the water carries less oxygen. You could put a small fan on the same timer as the light, which might knock it down too much; or just take measures to increase oxygenation.

[Adamant]

Thanks,

The PH is pointed at the wall just below the surface so there is lots of surface agitation, hopefully this results in plenty of oxygen content in the water!

Lighting is used just occasionally for feeding to keep stress levels lower, although I could put a fan on it's own timer. Won't this greatly increase my evap? I'm dosing with Cupramine and don't have an ATO on my HT so doing manually morning and night. Not much losses currently but wouldn't like the idea of overdosing!

Room temp is about 23C during the day according to my home thermostat. It's not by a window and no glass top on the tank.

If the fish will be OK with it then it's a week and a half left of their 3 week Cupramine at which point I'll put a fan on (along with putting some fresh sand in for my Goby, he looks pretty sad in the BB HT :( )