This doesn't seem good. After adding some CYA and borax at the skimmer, I noticed some CYA pellets on the bottom of the pool below the returns. Does this mean there is a hole in the sand? What do i do to repair?
Any chance the multiport valve was on recirculate?This doesn't seem good. After adding some CYA and borax at the skimmer, I noticed some CYA pellets on the bottom of the pool below the returns. Does this mean there is a hole in the sand? What do i do to repair?
Those CYA granules can stain your plaster (do you have a plaster pool? - please add to signature).
Brush them around now. Try to get them to dissolve.
You may have a channel in your sand. You need to Deep Clean to see if you can fix that.
You should never pour the CYA granules directly into the skimmer. Place them in a sock and hang in front of a return.
Take care.
Any chance the multiport valve was on recirculate?
If there was a hole or crevasse in the sand, CYA granules should still get stopped by the laterals. Just how big are these "pellets"? If they're bigger than a grain of sand and there's no sand blowing out, I'd look at the valve before I blamed the filter itself.
Typically, a bad multiport manifests itself with water dribbling out the waste port when it's on filter.I've been working on clearing water, and pump has been on 24/7 for about a week, including a few backwashes. I understand the logic about the valve. it is definitely not on recirculate. Good idea to check, but it is relatively new. It does seem like sand would be getting through if granules larger than sand are getting through. Spider gasket is relatively new as well. Multiport valve still turns very smoothly since being lubed last year. How can I tell if ports are not being closed off properly?
No leak via waste port.Typically, a bad multiport manifests itself with water dribbling out the waste port when it's on filter.
If you're not getting sand out of the returns, the cyanuric acid is probably getting out via an internal air relief tube that is missing a screen.
It might be a bad spider gasket segment. Sometimes only one leg of the gasket goes bad allowing debris to bypass the filter.
What model filter and multiport?
If the multiport is mounted on top of the filter, it's probably not worth removing it to check. Only a small amount of water bypasses the sand.
If the multiport mounts to the side, you can remove the top dome to check the air relief.
What model filter?
Actually vinyl could be harmed by the granules too. They are acidic.
I do not believe any one on the forum advocates pouring the CYA powder in the skimmer. You can put the sock with the CYA powder in it in the skimmer if you leave the pump running.
With a top mount multiport, you might not have an air tube.
It might be a loose fit where the multiport fits over the standpipe or a bad spider gasket or maybe a channel through the sand and a bad lateral.
You could remove the multiport to check everything but it's a pain because you have to cut the pipes and the multiport might be stuck on the standpipe and the standpipe can get pulled loose if you lift too hard.
As long as it's working, it's probably not worth taking apart. It's probably only a little bit of water bypassing the filter. The multiport might have a small air bleed hole but I don't know.