Try this...
Unplug your power head/pump or whatever submersible water circulator is in the tank. Leave it off for a few hours and check the temp. I had a penguin 550 in my 20 gallon and it made about a 4 degree difference in the water temp.
I now run a hagen 201 set to a low flow and a...
www.hellolights.com
I have MH from them and so far, I am happy.
Their DIY stuff is not all UL listed and you need some electrical experience to wire them correctly.
Enjoy,
Dave
You can always use the filter box built in the hood to run carbon or a filter pad as/when needed. It is already there. I would run it just for the extra flow.
