Detrimental Lighting

[atomiclord]

Ok so here's my problem, My moderately planted tank is about 20ish litres (about 5 gal) with 6 danios and some shrimp and snails. The plants need the light, but the lights in my hood (decided the one it came with was ok for now, tricky to replace) is heating my tank. I have to keep turning the lights off so that the temperature doesn't keep going up. I've not let it get above 30 degrees C (about 80 F from memory) but I'm worried about my fishies and whether or not my plants are getting the required light them turned off for an hour every four hours. The plants still get 12hrs lighting each day (timer system). Any tips on lowering the temperature of my tank?

[jcarlilesiu]

You could always put a small fan blowing between the top of the tank and the light to help move the hot air away from the aquarium before the light heats it up.

I have an open tank top with 2 HQI metal halides on top. I could probably cook eggs on top of my light fixture. The built in fans discipate that air before it heats up the water itself (or mostly)

[jsoong]

What light do you have? A 5 gal prob. won't have enough room to fit a fan in ..... unless you have a custom hood ...

If you are using an incandescent light, you'll do better switching to compact fluorescent. It gives more light for the plants, and is more efficient so gives off less heat. <You might have trouble finding a daylight CF that will fit in a small hood tho.>

[fort384]

Not a great pic, but here is how I control excess heat in my 5G. I have a little AC powered fan that is clipped to the side and blows across the surface. It is amazingly effective -- dropped my tank by as much as 3-4 degrees F. You can buy these fans many places online for fairly cheap. I think their primary purpose is cooling computers and electronics, but they work great for aquariums.

[mgamer20o0]

what kind of danios? could solve a couple things with one stone if you just got a bigger tank.

[atomiclord]

Yeah I have the huge one I could set up but I may be moving soon so not such a good option. They're zebra and leopard longfin danios. I will try keeping the lid open slightly so the hot air has a chance to escape. I'll post how well that goes. As for timing the lights to turn off for an hour everby four hours, that seems to keep the temperature down a good couple of degrees, and more stable. Which is more important anyway.