sand in AG pool from a dough boy filter

[mikew21]

hello this is my first time posting so ill try to get it right for everyone heres the problem i have i have a 21 foot AG and my filter is blowing sand back into the pool it is a dough boy model # 0 1701 013 if that helps
it only dose it when we start it up or after vacuuming and only dose it for 10 to 15 seconds or so but you can see it blowing in so its a bit of sand i do backwash and rinse after like i was told but it has not helped at all
I've took the top off and removed all the sand but im not all that sure what I'm looking at just a pipe and it gose down into a plastic compartment i guess you would call it i do intend to replace the gasket on the top as it was old and ugly if anyone can help with some suggestions that would be awesome
thanks a ton

 

[linen]

Welcome to tfp, mikew21

I am not too familiar with doughboy filters, but with most sand filters, the first thing to check is the multiport gasket, if it is worn it needs to be replaced.

 

[cramar]

I had a similar problem due to backwashing when the filter didn't need backwashing, another member suggested this and sure enough that seemed to be the problem.