CYA coming back through returns?

[kevincad]

I added some salt this morning and some CYA as is recommended (previous levels were about 30 but I had drained a good bit of water to lower the Ca level -- another story). Pool is about 35,000 gallons.

Anyway, I added it slowly to the skimmer (5 lbs over about 3-4 minutes). Then I notice that the returns are shooting some of this stuff out. It looks like at least 50% of it came back out the returns.

Shouldn't the filter get this? I initially thought I might not have added enough DE when I backwashed, but this stuff is much bigger than DE.

Any thoughts?

Thanks,
Mark

Make sure you have your filter set to filter, as opposed to recirculate or some such.

[HooStat]

There is only 1 setting. There is no way to bypass the filter. Water comes straight from the pump to the filter.

[mwsmith2]

Then something is very wrong with your filter.

Michael

[duraleigh]

Hoostat,

There is only 1 setting. There is no way to bypass the filter. Water comes straight from the pump to the filter.

The multiport valve would be AFTER your filter. Are you saying the water goes from the filter directly to the pool with no way to backwash, etc?

[HooStat]

The water comes from the skimmer and/or main drain and into the pump. From the pump it goes to the filter and then to the heater. From there it goes to either the infloor system or main returns (depending on valve settings).

For the spa, the setup is the same except that the water comes from the spa drains and goes back via the spa returns.

This seems like it should be pretty standard. Am I missing something?

Just added: backwashing is done by moving a lever on the filter. when I move the lever, the backwash goes into the drain instead of the pool.

[duraleigh]

Hi, Mark,

backwashing is done by moving a lever on the filter. when I move the lever, the backwash goes into the drain instead of the pool.

That's the valve we're talking about. We just wanted to make sure it has no other position than "backwash" and "filter". Many valves have several positions at that point including recirculate which does bypass your filter.

Sorry we got off the topic.

Anyway, unfortunately, I'm not a DE guy but you have something wrong with that filter. This post will bump you back to the top and get you noticed by a DE expert.

[rmeden]

Normally the backwash valve is considered separate from the filter (right before and after it). Maybe yours appears as a single unit.

I think you're right.. CYA is bigger than DE... if you didn't add enough DE it would still be caught by the grids.

I think you'll need to open your filter and check the grids for tears.

BTW, CYA disolves slowly... it normally is caught by the filter and disolves from there. If the CYA gets through, your filter isn't filtering.

Robert