hi guys, using a 20 gallon blaster for doing a mini shell, only put 25kg into it at the moment (got 2x more bags coming) of the blast media, but it seems to be sticking on the bottom and sides of the inside of the tank, i have to shake it when it stops or hit it with a hammer but it doesn't bring that much out. i usually get 3x small shovels when i brush up and sieve it back in. but when i disassembled it this evening i got 6x shovels out, i just can't understand why it is getting stuck around the sides when it is a smooth surface inside?