Looks great bro! I'm by no means the tang police, but I wouldn't recommend putting that tang in a 20. Taking it from an already small 40 and going down to a 20 will very likely, almost certainly stress the fish out. Tangs are extremely susceptible to ich when stressed and that'll wipe out every other fish in the tank. Just happened to a buddy last who took a tang from a 180 and put him in his 90... Three days later all of his livestock was done for
Keep up the great work though!
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