Opening Pool, time for new sand filter or filtration media?

[Craig727]

We are hoping to open our pool this week, it is suppose to hit 80 on Wednesday March 15. I have a couple questions I was hoping you experts could help me with.

Our pool is going on its fifth season. It is an inground fiberglass pool with salt water chlorine generator. The pump I have is a Jandy PlusHP PHPM2.0 - 2 (speed pump) matched with a 300# jandy sand filter, ST24-T.

Last season we noticed a lot of sand was ending up in our pool. I was reading that the cause of it could be some of the laterals were damaged. However, yesterday I emptied out the sand filter and inspected the laterals and they all seem in perfect condition, no cracks or breaks in any of the laterals. What else might be causing sand to end up in our pool? Pump oversized? The muli-port valve wearing?

We have always been happy with the water clarity of the sand filter, but since we have emptied out the sand is there any benefit to changing the filtration media from sand to Zeolite, or glass beads? If we stick with sand should we cover the laterals with pea gravel before filling with sand, something we didnt have previously?

Thanks for any help or suggestions.

 

[duraleigh]

Re: Opening Pool, time for new sand filter or filtration med

Last season we noticed a lot of sand was ending up in our pool.

How much? Are you sure it was coming from the returns? Did you put a fine mesh over the returns to confirm the sand was coming from them?

 

[Craig727]

Re: Opening Pool, time for new sand filter or filtration med

no we didn't put a sock on any return to check. However it would always appear at the bottom of the pool and "walk around" ledge below or just past the return closest to filter/pump. I seem to recall it being worse when we had the pump on high speed, either for heating or cleaning the pool. Otherwise we leave the pump on low speed 24/7 during summer.

I would guess about 1/2 cup to a cup before we swept it off ledge and put the robotic cleaner back in to vacuum it up.

 

[duraleigh]

Re: Opening Pool, time for new sand filter or filtration med

It might be worthwhile to check the condition of the Multiport gasket. You can take the multiport in half by loosening the screws around the body and carefully lifting the top. The gasket is a round "wagonwheel" rubber piece that should appear to fit snugly in the slot provided.

If that is in good shape and there is no damage to your laterals that you can see, I would suspect it may not be coming from the filter. Putting something over the return to catch the sand will prove or disprove that.

 

[Craig727]

Re: Opening Pool, time for new sand filter or filtration med

Just took apart multiport valve and the "wagon wheel" gasket looks to be in good shape. I did notice that pin for the selector handle was part way out. I cleaned everything up, drove the pin back in and reassembled.

Any chance the pump at high speed(2hp) is just too much?

If I stick with sand media, do I need pea gravel as first layer around my laterals?

 

[duraleigh]

Re: Opening Pool, time for new sand filter or filtration med

Any chance the pump at high speed(2hp) is just too much?

If I stick with sand media, do I need pea gravel as first layer around my laterals?

What is the gpm rating on your filter?

What approximate gpm are you getting from your pump?

What is your normal psi?

That's the only way you can tell if your over driving your filter.

I chose NOT to put pea gravel in my filter and, to my knowledge have suffered no ill effect.....it was an option - neither encouraged or discouraged by pentair.

Before you get too involved, I really would suggest confirming that sand is coming from your filter. We've had multiple instances on the forum where it was not.

 

[257WbyMag]

Re: Opening Pool, time for new sand filter or filtration med

To expound on what duraleigh was saying, we have had lots of reports of what looked like sand coming out of the returns that, upon further inspection, turned out to be algae. In the abscence of lateral damage, I would check for that.

 

[Craig727]

Re: Opening Pool, time for new sand filter or filtration med

It is definitely sand and not algae. I have read some of the other threads you mentioned looking for clues.

I just checked my pressure guage for my filter and it does not go to zero, ie it busted. I guess I dont really now what the operating pressure was running last year. I am heading up to the store to get new sand and a new pressure gauge.

I am not sure of my dynamic head pressure so, I do not know my pumps GPM on high speed. What is the best way to determine the pools dynamic head pressure?

Thanks for all the info.