what exactly do you mean by "strainer"?
the problem is that the intake tube sits too close to the sand. there are a couple of ways to fix this.
a foam prefilter on the end of the intake will help tremendously. though it will need to be tightly woven.
the best thing you can do, if youre handy, is a little DIY on the filter. because the ac30 is a bit bigger then you would normally use on a 10g, the stock intake tube is kind of long on the tank. you will want to shorten the intake, or otherwise move it away from the sand being kicked up by the filter. the easiest of which would be to simply cut the intake tube in half (or however long you want it) using a fine toothed hacksaw. then just add a prefilter the the open end.
the more effective way would be to reroute the intake using PVC or CPVC.