fungus & bugs - help

[mexorchid]

I was thinking already about heat mats but even the moist space types can't be submerged. The furniture I'm building for my plants has kind of a basin on top with a level so I can easily drain the water from the lowest point. I was thinking about filling the whole platform with LECA and water but then I can't use a heat mat... hmmmmm ... I need to think of something else to heat them. Maybe through the lights...