I just bought the Tunze 3155 ATO and plan on opening up the back and changing the adjustment dial to the nano setting (easter egg). Hopefully the evaporation won't as much as an issue. I woke up this morning and my return pump was almost dry and I thought I had enough in it to last another day or so. Had to manually fill it back up this morning with RODI water I bought from a lrs.The Kessil is right up there along with Steve’s LEDs On my list. I’m sort of torn of sticking with the hood and the sleek look, keeping evaporation low but possibly add fans to ensure temps are stable. To open tank with with something like the kessil and that shimmer but faster evaporation like you’re experiencing. Like a moth to a flame with the shimmer I guess. Lol.