coming along nicely. how big is that biocube (looks like an 8gal?)? at any rate, if you want to hide your heater in the back, a visitherm stealth just fits perfectly into the first chamber. just a thought; it gives a cleaner looking display with more space for coral

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how big is that mantis? O. scyllarus get big and will need at least 30gal when they are full grown... you might also want to consider the fact that they can break glass by the time they hit 5 inches or so.