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[mysnakesau]

So as its maintained regularly, a rinse even in the sink after washing up is as good as anything. Clean up his crap as soon as you obvserve it, will help cut down the amont of chemicals you would need. F10 is expensive but a good anti-bacterial agent, especially useful when you have more than one reptile.

With your fish tank, I wonder if you put it in a cardboard box (just big enough for it) and cut the front of the box out, whether that could help hold the heat and provide a more stable gradient. Don't quote me, but someone else might be able say whether or not this could work.