I have a 4 week old 7' spa sitting on concrete and noticed 4 small 2 inch cracks on 2 of the seats. the concrete is level but noticed it is no completely flat along 2 of the sides. 1 of the sides has a 1/4" gap running for 14" in length the other side 3/16" gap for 13". Is this the cause and if so how can I level/support this completely on all sides and middle on the concrete? If I slide a new complete layer of 8' 2x6's under the spa and lay them flat on the concrete will this surfice? Or is there any other sugestions? Thanks " title="Shocked" />

I'd say it was unlikely that a 1/4" tolerance in a concrete pad would cause a 4 week old shell to crack - I suspect you got the tub on eBay and its made in China.

Sounds like a warranty claim to me, if you have one.

If not, google: "Acrylic Repair Kit" - you can grind out the cracks with a dremmel tool and reseal, but it won't be pretty, and may not last too long...