| The sand/gravel filters I make have an air manifold in the bottom. You can attach a 1 hp spa blower or small shop vac to this and flush out all the trapped waste. Just pull the plug from the waste line, put it in the pond line and turn the blower on. All the trapped dirt will boil up and out the waste line. I really like these filters for finial fines filtration. I am using several on my ponds and highly recommend them. |