Pool filtering Problems?

Question

When I vacum my pool the green algea come back out the jet in the pool water The filter is sand style Why would it not filter through the sand and then back out as clean water

Answer 1

Sand is good at filtering out particles down to about 5 microns. Algae is less than five microns, so that is why you are getting it back into the pool.  You should really kill the algae before you try to vacuum it up. Shock the pool and then vacuum to waste, once you are sure you killed it all, and just because you can't see it doesn't mean it isn't there, so keep the chlorine high for about 2 days and keep it filtering for the entire time and backwash two to four times. You will lose lots of water, but better to add water than swim in algae.

Answer 2

Vac the algae on "waste" or "drain". It's such a small particle that it'll make it's way eventually through the sand bed if you have a lot of it and..as you've seen, back out the returns.