Very nice indeed...just wish you had a bigger tank for those tangs - and angel for that matter. Believe me when I say they will outgrow that 90 FAST. Especially if fed properly... (I'd argue that they should never be in a tank that small to begin with, but I know tons of people do it)
Another suggestion/comment...please don't leave the heater IN the tank. The last thing you want is stray voltage leaking into your system. If you don't have a sump, at least get a grounding probe.
Tangs and stray voltage don't mix well!
And I don't mean to sound critical, just wanted to give you my honest opinion. Other than those 2 things, I do LOVE the rockwork/corals! Good job.