Today, I got a new 20 gallon tank at Petco, and went to go set up the tank. After about 1-2 hours, I realized there was this weird smell in my tank

(it smelt like chemicals), then took my hermit crabs out, and set up a fan so that it would blow the smells away (pretty sure that was a dumb idea). Now it's almost 4 hours later, and the smell will leave, but then it'll comes back again. What do you think? I really hope I don't need to deep clean (although I probably will have to) because cleaning is always not fun,

but whatever makes my hermit crabs happy!

Will the smell go away on it's own, as long as I keep the lid off? How can I get rid of the smell (preferably w/o deep cleaning, but that is doubtful)?