I've got a spotted dragonette in a 40. no issues, except he was looking a little skinny a while back. I dosed some pods and got back on a regular phyto schedule and he's chunked back up. You have enough substrate and rock that you should be ok.As I’m tossing around ideas for further stocking, dragonets have come to mind. I know a mandarin would be very hard to maintain in this size tank, but what are your thoughts on a ruby red? With my luck, I wouldn’t be able to train one on frozen, so assuming that, would I still have to resort to dosing pods or does a 40B offer enough space?