rust sediment in pool

[bellini]

I did the bucket test on water from the hose before I filled the pool (from the same hose). We do have a softener but the majority of the water was from the outside tap, so not filtered; but I did add water toward the end from the house, so that did go through the softener. No other filters.

[PoolDoc]

Hm-mn.

A softener will remove iron from water, until it's saturated. It sounds like you have a mix of water sources: pre-softener, post-softener in fully regenerated state AND post-softener in un-regenerated state.

You need to bucket test your water, pre-softener. I'm pretty sure you'll see a different result. By the way, if you have iron in your water, you also need to be adding sodium hydrosulfite to your brine, before you regenerate. Iron will permanently foul the zeolite media, and result in greatly reduced life. (Unless, you have a greensand filter, in which case you regenerate with a potassium permanganate solution.)

Regardless, you've got several possible ways to go.

1. Clean up in place

2. Drain & refill, but dose with HEPD and polyquat, so you can gradually remove the iron, without having it all settle out.

3. Drain & refill with post-softener water, stopping to regenerate the softener as needed, to prevent iron 'break-through'.

REGARDLESS of how you go, better filter cartridges (Unicel or Filbur) will make a big difference.

+ The OEM cartridges in Intex / Summer Escapes / etc. filters are not high quality. The Intex manuals recommend replacing them completely every 2 weeks. A BETTER option is to replace them permanently with 2 - 3 Unicel cartridges, and rotating them through a cleaning solution. Properly maintained, the Unicel cartridges will last all season AND will filter better. So even though they cost more per cartridge, they cost less per season! Learn to maintain them, by reading this post, Cleaning-your-Cartridge-Filter-wiithout-Damaging-It!

But, purchasing them is tricky. Amazon does not consistently stock them, and some of the 3rd party sellers are charging high prices and/or high shipping. So, check the Amazon link, but watch out for the prices and shipping costs.

It would be nice if you could just buy them elsewhere, but many of the online pool stores are listing Pleatco or other Asian made low quality filters, as "Unicel C-4607 type" or "fits Unicel C-4607". So shop carefully!

Here are the Amazon links:

Unicel C-4607 Replacement Filter Cartridge (Easy Set Size A or C) @ Amazon
Unicel C-5315 Replacement Filter Cartridge for 15 Square Foot Intex B Filter @ Amazon

[bellini]

Thanks! We've had the water tested by 3 different places (because we were really trying to get our house water cleared up) and they all say low iron. But this is orange sediment that looks like rust. After researching I was thinking maybe it is iron-bacteria. The water tested in the bucket test was pre-softened and never changed color or got cloudy.

In any case, I didn't feel that the broom-vac we had was removing much of it, so when it all settled in the middle we used a shop-vac to suck up a couple of loads from the bottom. That did remove a great deal. Of course, then the problem is how do we replace the water lost? We used post-softened water from the house and since it was a small amount, I think it was clear. So now we are continuing a try-to-filter-as-much-as-possible method. If is pools in the center I can try the shop-vac, but if it is dispersed all over the bottom I can't shopvac without removing a ton of water and I am just stirring it up so it can be filtered and replacing the cartridges often.

My only remaining question is, when you say "dose with HEPD and polyquat", would this be useful now if I am not refilling? I'm pretty positive that I can not refill without having the same problem. Or if I am just working on filtering as much as I can (I don't think we'll ever get it all out), should I just stick to dichlor (which is so far all I've used). ??

[PoolDoc]

Rust bacteria are not, I believe, orange. In any case, persist as orange sediment in a chlorinated pool. Please understand that iron tests (a) are often inaccurate and (b) ONLY measure dissolved iron. By definition, orange sediment on the bottom of your pool is no longer dissolved.

I am getting the impression you have never bucket tested your well water BEFORE it went through any filter or softener. Is that correct?

Also, it's typical that wells with iron contaminated water vary from time to time and season to season with respect to how much iron is present in the water.

Regarding filling -- using the polyquat and HEDP AS YOU fill, followed by trichlor tabs in the skimmer, is intended to (1) kept dissolved iron dissolve for awhile (HEDP), (2) help clump and filter the iron as it changes from soluble to insoluble forms (polyquat), (3) allow you to remain algae free while maintaining relatively low chlorine levels (polyquat), and (4) 'push' the iron to make the change from soluble to insoluble, just upstream of the filter (trichlor tabs in the skimmer).

[bellini]

Oh Ben, you are so patient with us novices. Well, would you believe that we do not have well water? It actually does come to us treated. Though, it does make sense that iron tests only measure dissolved iron and maybe that's why our levels seem low. I did do the bucket test on pre-softened water, but it did go through a sediment filter 1st - one of those that looks like yarn wrapped around a tube - which obviously gets overwhelmed quickly, hence all the sediment. Anyway, I think I will have my husband climb into the crawl space to get us some unfiltered water to do a bucket test, just to see. And in the meantime we'll keep filtering!

[PoolDoc]

Just take out the cartridge filter, run enough to purge the lines, then grab a sample, and reverse the process.

Or not.

If you have old iron lines, the situation is different. Iron can be released into the tap water continuously -- I assume your cartridge shows up orange? But, it can also be introduced in large quantities, on a no-notice basis. Among other occasions, this will tend to happen anytime the fire hydrants are used or a water main breaks . . . or even is just closed. So, depending on when you collect the sample, it may not tell you anything. The condition of your particle filter will tell you more. Orange = iron.

Also, with water lines, you may be introducing insoluble iron particles directly.

The good news is, this sort of iron can be handled even more effectively than well water simply by filling SL-O-WLY via the skimmer with the pump running. But, using HEDP and polyquat will help.

[bellini]

Thank you! Yes, we have orange filter cartridges every time. Actually our pool pump can only run for about an hour and a half before it is too clogged and orange, so we can't keep it running continuously but have to monitor it. So I think we still have a long way to go before we ever get the pool cleaned up and may not resolve the problem this pool season, but at least we have a better idea of how to fill it without causing this problem next year. Thank you!