advise just bought 72 gallon bowfront

Clown loaches can get to about a foot long. Not only that its really only good to keep them in groups. They are awsome fish, but i wouldnt get any for a 72 gallon, unless you wanted to get rid of them in a couple years . : (
 
The lighting is fine, it's on the upper end of the K range for my liking, but should work fine. I prefer 6500K, but it's just a personal choice. You are in the low-very low range though, just over 1wpg. An extra light wouldn't hurt.
 
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