Non compressive shims
 

I am trying to find composite shims here in St. John's, but no hardware store seems to sell them. Anything else as a substitute? Using them to level a 220 gallon tank.

Thanks,

Chris

Just buy a chunk of maple (or any hardwood) , and cut your own. Just make sure the grain is lengthwise in the shims:)

try a plumbing wholesaler, they have toilet setting shims, work great.