Sand coming out of pool filter when backwashing typically means old sand broke down or bad laterals broken or cracked letting sand go through.
A little sand in backwash is not new. A lot of the packaged sand filter systems utilize pumps whose flow rates is way bigger than the filter capacity flow rate.
I know what you’re probably thinking – the more horsepower the better, right? – Wrong! This is not the case.
If the sand comes out during back flush then the pump is too strong or the sand level is above the beginning of the rounded top of tank. The sand level will eventually correct itself.
How to FIX Sand Coming Out of Pool Filter When Backwashing
It could be broken laterals but it may be as easy as running your system on “rinse” for 30 seconds after you backwash. However, if there’s lots of sand coming out, and your pump is sized properly with the filter, then you might have broken lateral drain assembly/bottom manifold.
However, if you only get sand blowing back into your spa after you backwash, then bad laterals are most likely the issue here. If debris that’s returned ends up getting stuck in the filter as soon as it goes back into the system, it simply needs some rinsing and placing back in filter mode.
If your unit doesn’t have a “rinse” setting, then just brush it into the drain, with the pump running, after your backwash.
ALSO SEE: Is Your Summer Waves Pool Pump Leaking? QUICK FIX!
How to Change Sand in Your Pool Filter
- Turn off power, close off the lines (skimmer and return with the plugs)
- Take off the cap and drain the filter tank
- Unhook the multi-port.
- Turn the center piper a bit (so that the pipe that returns the water to the pool).
- Pick a flexible cup and a bunch of buckets (SEE ON AMAZON) and take away the sand
- Put the cap on the drain at the bottom of the tank
- Cover the return pipe with Aluminium Foil & gallon ziploc
- Fill the tank 1/3 full with water
- Put new sand in the tank.