Cartrig filter not filtering very good

[Rg1954]

I have a American commander cartridge filter 150 square feet 1.5 HP pump it seems a lot of water comes through unfiltered is there is there a bypass inside the filter is this normal. If I vacuum the bottom of the pool and discard the water everything if fine if I return the filtered water to the pool the water becomes cloudy

[Denniswiseman]

I suspect it's a dodgy cartridge
Vacuuming to waste doesn't go through the filter

[Teapot]

1.5hp pump on a 150ft filter is a bit overkill at first read. As you have a spa is the pump required to provide strong jets for the spa?

[Rg1954]

It's a 16,000 gallon pool is the filter too small

[Teapot]

Probably but the pump is definitely too powerful, l would suggest a speed controller to reduce the power. Is this pump used to provide the spa jets?
On a sand filter setup and to an extent DE, you need the power to dislodge dirt etc on backwash. Cartridge on the other hand doesnt need this. Slower flow = better fitration. Dont know what micron size your cartridge filter is but even not knowing if you supply enough force (1.5hp) you can squeeze and force dirt through a media and back out into the pool. A chef filters a consomme slowly throgh a filter to get the liquid very clear, if he squeezed the cloth it would become cloudy, same with pool filtration.
When I setup a spa for a customer I use a small pump to filter and an independent second pump system to power the spa jets so it doesnt ruin the great filtration we have achieved.