Filter from the sand filter to the pool

[Charlize]

hi,

I have sand going out into the pool. Can I put an extra small filter along the pipe from the sand filter to the pool?

BR, Charlize

 

[Jezza]

Have you had a look inside your sand filter? The sand might be coming from your filter due to a cracked/broken lateral.

 

[Charlize]

Have you had a look inside your sand filter? The sand might be coming from your filter due to a cracked/broken lateral.

The laterals are ok, we checked.

 

[Texas Splash]

Not sure of any additional methods to catch sand. If you've ruled-out the laterals, some other possible explanations might include:
- Too much sand
- Wrong type of sand (not #20 silica pool sand)
- Too much pump pressure

 

[Charlize]

I suspect the sand might be too coarse, but i dont know if that could cause sand to go to the pool?

Another theory: the big valve connected to the sand filter (the valve i turn to backwash etc), could wear and tear on this valve cause sand to leak to the pool?

 

[Texas Splash]

Yeah, I didn't mention the multiport valve or spider gasket inside it, but there's always a chance it needs some work. In addition, does your filter have an internal air bleed? In many filters, there is a small pipe/tube (about 1/4-1/2" in diameter) that connects to the outlet that has a suction strainer (screen) on it that provides an internal air release. Sometimes those screens either break or go missing, and can cause sand bypass.

 

[Charlize]

I dont know if my filter has an internal air bleed. where in the filter would that be? do i need to take all sand out to check it?

If someone could tell me what problems too coarse sand could cause i would be grateful.

Thanks, Charlize

 

[singingpond]

Have you made any changes in the filter lately, any maintenance, new sand, anything like that? Is the problem of sand getting into the pool of long standing? Or is it something new?

 

[Charlize]

Ever since the pool was built 7 years ago we had some sand come out, but it wasnt a problem until recently. the last year it has gradually gotten worse. then 3 months ago we changed the sand. the company who built the pool sent us sand, it said sea sand, but it didnt say the size on the bags. We live remotely so we have a very hard time getting a pool company to come here to examine our system.

 

[singingpond]

So, perhaps your new sand is not actually the proper size for pool filter sand. Have you been vacuuming up the sand that ends up in the pool? I wonder, if you were to vacuum to waste instead, whether the situation would improve over time - essentially getting the smaller sand grains out of the system entirely...

Can you give us an idea of the quantity of sand going into the pool, say daily, or weekly?

 

[Charlize]

So much sand has come out that we have used a shovel to get it out. last week we opened up the filter and it was almost empty of sand. (so the filter emptied itself over about 3 months). It seems to have calmed down a bit, but sand is still coming out. But can too big grains cause sand to go to the pool, or is something else going on?

 

[singingpond]

I was thinking more that the sand might be too fine for pool filter sand. If the filter is indeed almost empty at this point, perhaps you should take the opportunity to inspect the laterals for damage or cracks that could be allowing the sand to pass. When you changed the sand, maybe some of that assembly was stressed or cracked in the process.

If you could find an online parts list for your particular filter, that might allow you to check on the part that Texas Splash mentioned earlier (the tube with the strainer screen), to see if your filter is supposed to have one of those.

Interesting thread about sand, which may or may not be relevant to your problem:
My findings on how not all sand is created equal

 

[Kiss4aFrog]

If the sand is too course it would not filter properly and your water might be a bit cloudy all the time but it would stay in the filter. If it's too fine then it might be smaller than the openings in the laterals and be able to get push out into the pool.

 

[Charlize]

we put the sand back in the filter about 6 days ago. I did look at the laterals, all looked fine. I think i need to see sand with the proper corn size so i can compare to what i have. im starting to think the problem might be the mp valve.