Lance's 225 gal tank

[Lance]

Sitting on the couch tonight watching TV and I hear a loud crack from the big tank: exactly like glass cracking. Oh ****! I check out the tank but cannot find anything. No leaks, no cracks that I can see. Kept a close eye on it for the better part of an hour. I'm thinking, and hoping, it was the light fixture. The noise came about 15 minutes after the halides went out so maybe the metal cooling down caused the noise. Hasn't happened before though. Going to bed with my fingers crossed tonight. Will set my alarm for 3am and check things out.