If you’ve got iron in your fill water, use Polyfill to remove it

lightmaster

TFP Guide
Jun 22, 2017
801
Baxley, GA
EDIT: Found out this method only works if your iron is oxidized already, meaning it’s got a dull or bright green tint to the water, or a nasty brown tint. If you know you have iron in your fill water, but it isn’t oxidized yet, bring your pool to shock level and it’ll turn the telltale green, then you’re ready for the Polyfill.





My well water has iron in it, enough that when I add chlorine into my pool, it oxidizes the iron and turns the water a dull green color. Everyone said I needed to add in a sequestriant to sequester the iron, but that it wouldn’t actually remove it from the water, and that I’d have to keep adding the sequestriant every month. Not wanting to add any more chemicals to my pool than I need to, I read about using polyfill to filter the iron out of the water. Not having a skimmer to fill with Polyfill, I rigged up a 5 gallon bucket to my pool ladder with some string, have a couple dozen 1/4” holes drilled into the bucket, and a large hole drilled into the bottom of the bucket. The bottom hole is just big enough to let the smaller end of a vacuum tube fit into and about 90% of the way down the tapered tube, it seals tight. I then got a piece of PVC pipe that just barely fits inside the return hose and the vacuum tube (both happen to be exactly the same size), connecting both the tube and the hose together. Not wanting to ruin the only hose I have for my pump, I wrapped the rigged up connection with duct tape, then sprayed rust-o-leum rubber spray around it and gave it 5 mins to set, and then wrapped that with duct tape again. I repeated this 7 or 8 times and, once pressurized by the water from the return hose, only leaks at a rate of a single drop every 8 or 9 seconds. Again, don’t want to ruin my pumps hose, so that was the best I could do. Also sprayed the rubber spray around where the bucket and vacuum tube connect. After half a day of drying time, I opened the bucket and stuffed it with as much polyfill as I could, which came to about half the big bag I got from Walmart. That stuff starts expanding when compacted pretty quickly, so had to carefully close the lid without any sticking out. Now set the bucket on the pool ladder (strings tied across underneath bucket if you can’t use the top rungs) and use another string to hold the bucket steady. If you have a small pump that might tip over or has short hoses on it, tie it down on top of another bucket filled with water (I used cat litter container). Also tie your hoses up to give some extra support if needed. Unstop your intake holes, prime pump, and then watch clean water come pouring out of the holes in the bucket. Let it run like this for a couple days depending on how dark the iron has made your pool water. You should notice a difference within a day. If its bad enough that it fills up the polyfill (not sure how you’d know without taking down the bucket and opening it since mine wasn’t bad enough to have to change the polyfill), replace the polyfill every couple of days. Soon, you’ll see the bottom of your pool, and then you’ll end up with clear clean water with the iron actually removed from your pool, without needing to buy something monthly for it.

I will end up fixing the bucket so I can hook up a garden hose to it to top off my pool when low, and filter out the iron then before it gets into my pool again. Also, as I experienced, if you turn off your pump or it loses power, when you turn it back on, some of the brown iron water will start pouring back out because of the iron settling down to the bottom when the water isn’t moving. 10 seconds later, the water coming out of the bucket was clear again and within an hour, all the brown water that had been dumped back in was filtered out again. When your pool is back clear, you might notice some iron deposits sitting on the bottom of the pool, be sure to brush those deposits so your pump and pull that through the polyfill filter.

When you’re finally done and have a clear pool again, have someone else stop up the intake holes while your turn your pump off and then quickly get the bucket down before it runs out of water. This prevents any iron from settling to the bottom and spilling out into your pool. As a warning, be careful taking the bucket down, since its now filled with iron and water and is probably heavier than you’re expecting.


I’m attaching photos of how I rigged up the bucket, what the water looked like when I turned off the pump to check the filter and some iron spilled back in, and what it looked like when finished.


Here’s a link to the Photos Album containing my pictures of my setup to filter the iron.


Didn’t think to take photos beforehand, imagine my entire pool that green color.



This is my setup with it finishing up cleaning out the iron.



This is the holes in the lid and shows what my water looked like after filtering.
 
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niteshift38

Silver Supporter
Bronze Supporter
Jun 10, 2017
186
Hamburg/NY
AWESOME !!!! Great detailed explanation and photos. Creative ideas from contributers such as yourself are what help to make this the ONLY go-to site to truly take control of your pool. I'm already imagining other possibly uses for your innovative design. THANKS :)
 

lightmaster

TFP Guide
Jun 22, 2017
801
Baxley, GA
I don't know what all else Polyfill will filter out, but could possibly help with high levels of other metals too. If anyone does this, definitely check the levels of everything afterwards in case it filters out some of your CYA or alkalinity or something. Actually speaking of which, I need to test my TA to see if it dropped any, be pretty cool if this could help reduce high levels of TA or CH that are normally hard to reduce or require draining and refilling.
 

lightmaster

TFP Guide
Jun 22, 2017
801
Baxley, GA
Tested my water, TA and CH are the same as before, so didn't effect them. CYA was added right after taking down the bucket, so no idea if it effect that.

- - - Updated - - -

Wow. This should be a sticky in pool school. Make a video of how to hook this up to a garden hose so we people can filter out metals without them ever going in the pool
I'll make a video when I setup the bucket when I get paid again.

And while it definitely filtered the iron out of my pool, I don't have a copper problem, so I don't know whether or not it will filter copper.
 

lightmaster

TFP Guide
Jun 22, 2017
801
Baxley, GA
Just a follow up, its been about 10 days now since I've filtered out the iron from my pool and its still as blue and pretty as can be. Haven't had to top up the pool any from the well since its rained so much lately that every bit that's been splashed out has been replaced, and then some.

 
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Swampwoman

TFP Expert
LifeTime Supporter
Apr 27, 2012
3,835
Grand Rapids, MI
I commend your ingenuity and its a great way to get out iron that has OXIDIZED.

However, for posterity, I should share that there are usually TWO types of iron in well water - Ferric (if oxidized) and Ferrous (soluable in the water.) your filter will NOT capture iron in the ferrous state.

By suggesting that people not use sequestrant, you would be allowing ferrous iron to possibly stain or tint the water after if a person's PH gets too high or they slam the water...or if over time, the concentration increases.

Also, poly fill is a vastly inferior filtering media compared with reducing filters such as the 10" Pentek reducing filter, which first reduces to 25 microns, then to 1 micron and can be set up on a fill hose using some conversion plumbing connectors.

Just wanted you, and anyone who reads this thread, to have the full picture.

Cheers nonetheless to a partial solution, if you'll excuse the pun ;)
 

rwood5093

Bronze Supporter
Jun 5, 2016
86
Jamestown, SC
Have you actually tried it on water right from the well?

I'm curious to how well this would work. We have 2.1 ppm of iron, and I thought the iron oxidized when it mixed with chlorine. though if I fix a glass of water, it will turn slightly dingy. When we filled our pool, it was only after raising to slam level that the iron drastically oxidized. At that point, our pool was pea soup green but became crystal clear using the 5 gallon bucket filter. Mother nature tops it off, plus some.

What comes out of the tap doesn't appear to have as much iron oxidized. Have you tested it to see if it gets the iron out? Or is it only after it mixes with chlorine and oxidizes?
 

lightmaster

TFP Guide
Jun 22, 2017
801
Baxley, GA
Have you actually tried it on water right from the well?

I'm curious to how well this would work. We have 2.1 ppm of iron, and I thought the iron oxidized when it mixed with chlorine. though if I fix a glass of water, it will turn slightly dingy. When we filled our pool, it was only after raising to slam level that the iron drastically oxidized. At that point, our pool was pea soup green but became crystal clear using the 5 gallon bucket filter. Mother nature tops it off, plus some.

What comes out of the tap doesn't appear to have as much iron oxidized. Have you tested it to see if it gets the iron out? Or is it only after it mixes with chlorine and oxidizes?
I haven't yet tried it on straight from the well, and from what swampwoman said, it wouldn't work anyway since that iron hasn't oxidized yet. I'll probably get a reducing filter then to attach to my hose if I ever need to add more, which doesn't look likely anytime soon with all this rain.
 

lightmaster

TFP Guide
Jun 22, 2017
801
Baxley, GA
I've tried it, my pool is only a year old but I haven't had a single problem with the pool water yet.

View attachment 66066
You don't by chance have a link for that filter do you? Been looking on Amazon, but I've never bought a reducing filter before and not sure exactly which one to get. From what I can tell, you buy a filter housing and the filter separately on Amazon, right?
 

Swampwoman

TFP Expert
LifeTime Supporter
Apr 27, 2012
3,835
Grand Rapids, MI
This filter reduces from 25 micron to 1 micron and still gives good flow in my 10" Pentek Big Blue filter housing that I've rigged up to my fill hose:

I'm posting it because its hard to find the right one. Essentially, its a sediment filter, but small enough at 1 micron to get any oxidized iron. The spec name is Pentek DGD-2501.

https://www.amazon.com/Pentek-DGD-2501-Polypropylene-Filter-Cartridge/dp/B0014C09XG/ref=pd_sbs_328_2?_encoding=UTF8&pd_rd_i=B0014C09XG&pd_rd_r=9XKG4HYQ5P9SYEESS7MB&pd_rd_w=pwt7o&pd_rd_wg=10TDT&psc=1&refRID=9XKG4HYQ5P9SYEESS7MB#feature-bullets-btf

This is the link to the filter housing - note that to install it on a hose you will need to get a fitting from your local hardware store:
https://www.amazon.com/Pentek-150237-Filter-Housing-Female/dp/B00BI4HXJ8/ref=sr_1_1?s=industrial&ie=UTF8&qid=1500463368&sr=1-1&keywords=Big+blue+10%22+Pentek

Hope that helps ;)

To Rwood - My well has 2 ppm iron. I've never tried it with just the Pentek because even if it got 50% of it, too much would be going in.

What I've done is plumbed the pool spigot to the whole house softener. That gets me down to about .5 ppm. Which still stains. So I put the big blue on the softened water spigot and that gets me down to around .3 ppm .... Right on the margin of staining ;)

BUT the softener and pre-filtering DRAMATICALLY lower my sequestrant need/useage, which on raw well, was super high.

I run my pool quite warm, with cold nights in Mich, so I loose a few inches every couple of weeks to evaporation and ergo need to refill. This helps me prevent iron accumulation over time, and the filter and housing are cheaper than what a weekly bottle of sequestrant would be. Now I use about a quart a month instead of a quart a week ;)

The benefit you guys have who've HAD to filter out tinted water is that through slamming, you've oxidized and removed much of the iron so your future accumulation will be slower ;)

It could be argued that it might be more cost effective to just boost your FC every time you top up with well water and run the Polyfill bucket. Or the Big Blue on a aux pump loop - I've seen someone set something like that up with the big blue.
 

rwood5093

Bronze Supporter
Jun 5, 2016
86
Jamestown, SC
I haven't yet tried it on straight from the well, and from what swampwoman said, it wouldn't work anyway since that iron hasn't oxidized yet. I'll probably get a reducing filter then to attach to my hose if I ever need to add more, which doesn't look likely anytime soon with all this rain.
That's what we used. A hose end filter. It did OK, but it didn't get all the iron. The water overall never changed color, but the filter was definitely getting rid of it for about a week. We only had to top off once, thanks to more than enough rain.
 

lightmaster

TFP Guide
Jun 22, 2017
801
Baxley, GA
I'm posting it because its hard to find the right one. Essentially, its a sediment filter, but small enough at 1 micron to get any oxidized iron. The spec name is Pentek DGD-2501.
So the reducing filter still only gets oxidized iron? Wish I could find a solution to filter non oxidized iron. Guess I'll just have to set up the bucket to connect to pool hose without leaking in case it ever stops raining, lol. Good thing is I plan to be upgrading to a Cartridge filter, so no losing water to backwashing.