Retest FC 1 hour after the tabs dissolve. I am thinking you need more cal-hypo but retesting will tell you. Get FC up to >5.0 SOON !
Please don't backwash (rinses out DE and calcium layer) until you absolutely have to. (don't vacuum to waste either)
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Retest FC 1 hour after the tabs dissolve. I am thinking you need more cal-hypo but retesting will tell you. Get FC up to >5.0 SOON !
Please don't backwash (rinses out DE and calcium layer) until you absolutely have to. (don't vacuum to waste either)
I agree that you should keep FC at or above 5ppm. Use the cal-hypo tabs to maintain FC at 5.0ppm. Let us know how the pool responds as pH and FC rises.
So, this am pH 8, FC >>5. Pressure at filter and water appearance unchanged.
Slowed return by approx. 50% by adding more DE (used an additional 1/3 cup).
Water began clearing. Vacuumed to filter until began to come out of return.
Backwashed when psi increased and flow slowed-rust in discharge.
Then added 1 cup each DE and polyquat. 1 cal-hypo in each basket.
Will check in am.
.
I am optimistic! Good job! Did you adjust your pH down a tad?
It still may take a while, but keep up with the system: DE, cal-hypo, and holding off on back-washing until you must. It sounds like the filter is working just fine. I could be wrong, but I think you might have just been back-washing/vacuuming to waste too often for the system to work.
Don't hurry, but next time you are at the hardware store, get a new, large white bucket (usually in paint dept for under $5). When you stop seeing symptoms of iron you will want to run a metals-bucket test to make sure it's gone. Here's the link so you can begin reading up:
http://www.poolforum.com/pf2/showthr...est-for-metals
pH 8.0, FC >>>5
Lower pH to what level? Do I want Fe back in solution? What would that do to captured Fe in filter?
Felt like filter couldn't capture/hold Fe until flow decreased significantly.
Can you get it down to 7.8? You do need to keep iron in solution, so just a tad.
Hard to tell about the filter cause more than one variable was changed... Just keep up with what you're doing unless an expert chimes in. Your method seems to be working. I am not very knowledgable about filters but I did have PoolDoc holding my hand through the process of removing my iron. He wanted my pH no higher than 7.8.
By the way, just curious. What part of Virginia are you from? My son goes to college there and I spend a lot of time in-state. (Headed there Saturday, actually)
How high is the FC? Is there any CC?Quote:
Originally Posted by stcohen
I would wait until FC drops back to 5 and the filter must be backwashed then backwash, bring pH to 7.6, replace DE, start chlorinating with cal-hypo again.Quote:
Lower pH to what level? Do I want Fe back in solution? What would that do to captured Fe in filter?
I agree, this is good.Quote:
Felt like filter couldn't capture/hold Fe until flow decreased significantly.
Improving slowly. pH now at 7.8
I can see this will take some time but I think I've got the filter working thanks to the DE. Think I had been going in circles until able to reduce flow which improved the sand filtration.
Live in Mathews, VA... near Chesapeake Bay. Lived in Richmond, VA mostly but retired to our river home last year.
Thanks for your help and support.
Your years of pool ownership paid off figuring that out! BigDave was wondering about FC and CC. Any numbers for him?
I got off topic with VA. Sorry, but I love VA. I still have some living relatives there; the rest of them are in Hollywood Cemetery... My SAR and Jamestowne Society (1620) son wanted VA for college. Got accepted at Univ of Richmond, William and Mary, Washington and Lee, and Bridgewater in the Shenandoah Valley. He chose Bridgewater for many reasons, mostly because he made the tennis team. He also made both the tennis and golf teams at VA Weslyan but chose the mtns over the coast. Ok, I'm done.
No obvious improvement overnight. Pressure up 2-3 psi so probably caught something.
pH 7.8 - 8.0
FC 10
CC 0.5
Not sure what to do right now.
Apply liberal doses of POPP (Pool Owner Patience and Persistence).;)Quote:
Originally Posted by stcohen
I'd keep the pump running until the FC works it way back to 5 or the flow is too slow to skim. Then backwash, replace DE, drop pH to 7.6, add cal-hypo to skimmer.
Thanks
That POPP is hard to come by... apparently not available at Amazon but I will work on it.
Look again, it's in the same category as the round tuits.
Not sure where you are with the pool, but a couple of quick comments:
1. GREEN cloudy water is algae. ORANGE cloudy water is oxidized iron. GREEN clear water is dissolved iron. BUT . . . you can have green clear water (iron) with algae and all you will see is green CLOUDY water.
2. It's possible to have dissolved iron with FC=3 and pH=8, but not likely. It can only happen if the iron is bound with VERY strong chelation.
3. With a sand filter, you should NOT backwash unless you see at least a 3 - 5 psi increase in pressure, over the 'clean' pressure. When you are trying to filter fine particles, you may need to allow pressure to reach 10 psi more.
4. I'm a little suspicious of your filter sand. Quite a bit of sub-spec sand is placed in sand filters. If it's not too hard, I'd recommend buying a bag of LABELED filter sand from a pool store (not: Lowes or Home Depot). Then open your filter, and extract a cup of sand. Let it dry, and then spread several tablespoons of the real filter sand and the sand from your filter on a dark smooth cloth, and compare.
@PoolDoc: Good to see you back. I've been concerned about the opacity stochen is seeing. I don't know if it's iron in solution + calcium cloud or iron in solution + algae or just algae. The filter was passing through orange iron sediment and possible calcium before OP started adding DE - enough to noticably reduce flow. It did produce calcium and orange sediment on backwash after adding DE. This pool has seen some periods of low chlorine. I've been reticent to advise shocking the pool for fear of staining - AFAIK there's only been one backwash that clearly produced iron.
Attaching 2 pics. One was 1 week after new liner and filter sand, the other is now. Sand was from pool store run by man that installed liner. Saw the bag, said pool filter sand. Not sure I know how to get inside filter. Overcast today with reflections from trees.
Initial brown cleared in about a week. 3 inch rain, appeared to have algae. Shocked and precipitated what I thought was iron. More shock only made it worse. Thought between polyquat and high FC it must be metal. Without softener toilets, clothes etc in house all stain. Do not have softened water at the pool.
http://plus.google.com/photos/110081...KG3lr3WhteKmgE
https://lh4.googleusercontent.com/-a...ial%2Bweek.jpg https://lh3.googleusercontent.com/-x...889-no/now.jpg
It's algae.
It *might* be algae PLUS iron. But it is algae.
1. Make sure your filter is working and your pump is on 24/7
2. Run a full set of K2006 tests (FC, CC, pH, TA, CH, CYA) and post results.
3. Begin raising your chlorine level, 5% every 12 hours.
For example, if your CYA is 40 ppm and your FC is 2 ppm, you are currently at a 5% level. Take it up to 10% (4 ppm), then 12 hours later to 15% (6ppm), etc. Stop at 25% if you don't see a color change.
Just tested
FC 4.0
CC 0.4
pH 7.4
TA 60
CH 170
CYA 30
Guess I need the specific order of things at this point. Shock? Use cal-hypo or Cl with CYA? Correct TA? Filter on 24/7 since opened
will go with bleach until told otherwise
I agree with PoolDoc. That's algae.
It seems like you can put a lot of chlorine in the water with those cal-hypo tabs. I'd use them and bleach to get the FC to 10-15 and keep it there until the green turns blue.
What he said . . .
As I've gone back and read this thread two things pop out at me:
1) Ben said bring pH down to 7.0 yet BD and FBU kept insisting it should be between 7.8 and 8.0 so it precipitates. Yet I thought the point of the cal-hypo was to get the dissolved metal to stick to the calcium and be captured in the filter. I'm confused by this.
2) It's no surprise that when you use large amounts of Polyquat your FC drops like a stone. A quart in a roughly 20k pool will drop FC from shock levels to very low levels, 1-2ppm in 48 hours. It's always something to be aware of.
BTW, that's the "ugly" green of algae, not the "pretty" green of metals.
Ben, Lisa recently found the old thread of a couple who invented a filter gadget that does the same thing as the auxiliary Intex pool....a filter system of lots of quilting batting that sucked the metal right up! I THINK it was using a five gallon bucket with a lid, a submersible pump and some hose.
@CarlD: I'm pretty sure that dropping the pH is for starting the metal removal process and get and precipitated metals into solution. Next step is holding them in solution with HEDP. Then remove metals with CuLater or using cal-hypo in the skimmer to encourage metals to come out on the filter by creating a high chlorine / high pH zone before he filter.
That's what I thought, but I thought the high FC/pH was to be local to the skimmer, not the whole pool.Quote:
Originally Posted by BigDave
During the process actually backwashed a total of 4 times that produced what looked like rust. Pool was improving then turned dense green. Did not think algae with the high FC and polquat. Did notice a pH drop day after using polyquat-just brought it back up with cal-hypo. Today
pH 7.6
FC 14
Still green, maybe a little less dense. Placed a Culator in trap in case residual Fe.
Polyquat isn't acidic, as far as I know. It WILL drop FC. However, if FC is very high, it causes a false high pH reading--we warn against this all the time. When Polyquat brought the FC far down, the apparent lowering of pH would simple be a true reading.
I didn't go back and re-read, so I'm not sure what I said.
But normally, you'd want to manage metal removal by STARTING at low pH, with HEDP present, and then gradually allowing pH to move upwards as cal hypo is used.
The goal is to FIRST get the metal dissolved (Vit. C with no chlorine), SECOND to keep it dissolved (low pH + HEDP), and then THIRD to gradually remove it on the filter, while avoiding sudden changes in pH or FC that could re-stain the pool (gradually increasing pH & FC + cal hypo upstream of the filter).
When Stcohen's pH reached 8, I encouraged him to lower it a tad to "no higher than 7.8". I sincerely hope I was correct on that.
Water described as green but not opaque, then "unchanged" over several days. However, his FC did drop at least once to 1.0.
What were results of sand test, Stcohen?
pH 7.4
FC 15.5
CC 0.5
Did not test sand, reluctant to get into filter
https://plus.google.com/u/0/photos/1...03381349070305
Any improvement in the water quality?
Turquoise instead of green. Trying to attach pic.
https://plus.google.com/u/0/photos/y...54816375647908
permissions aren't set correctly on the photo or image album.
About pics, not sure what I did different but will try again tomorrow. Must be the algae from hell. Not much improvement until raised FC to 30 and then slow at best. Had to leave town today but will return tomorrow afternoon.
Up to 30, huh? Did any iron staining appear?
I figured out what was happening with the pictures, but it's too complicated to explain. I need to post detailed 'how-to' post pictures using each of the different services this winter.
Judging from the yellow-green color, it looks like you have fully 'bloomed' mustard algae. Unfortunately mustard algae is notoriously hard to kill.
IF your pool is not leaking, you may want to go the low phosphate route. BUT you have to understand the limitations of this approach:
1. Lowering phosphates *some* is USELESS! It ONLY begins to be useful once your phosphate level is below 0.125 ppm (125 ppb). So . ..
2. You MUST be able to test accurately. For that, you need this: Taylor K1106 Phosphate test @ Amazon
3. Low phosphates do NOT kill algae; it just slows algal growth, making it EASIER to kill or control algae.
4. Many of the phosphate removers sold are over-priced and under-powered. The best is PR-10000, which is hard to find. SeaKlear has a product that appears to be almost as good: SeaKlear Commercial Phosphate Remover For your pool, you'd want to buy 3 quarts, to make SURE you have enough.
5. Using a phosphate remover often clouds the water; you may want to use this clarifier: GLB Clear Blue Clarifier
6. You'll ALSO need to test your fill water. Most tap water has 1 - 4 ppm (1,000 - 4,000 ppb) phosphates added as a corrosion inhibitor. This means you'll need to add small matching doses of phosphate remover EVERY time you add fill water.
7. Removing phosphate is NOT an instant process. The reason seems to be that the lanthanum FIRST combines with carbonates in the water (clouding the water) and THEN the lanthanum carbonate gradually changes to lanthanum phosphate, releasing the carbonates back into the water. This seems to take 3 - 7 days. During this time, if you clean your filter, you tend to lose the lanthanum carbonate on the filter, before it can be converted. So you need to (a) clean the filter, (b) add the PO4 remover, (c) set the pump to run 24/7, (d) wait at least 3 days before cleaning the filter again. THEN, you test the phosphate levels, and repeat if the PO4 level is not below 125 ppb.
8. Total cost on your pool for the kit, PO4 remover and clarifier will be ~$150. Hopefully, you will have some PO4 remover left, possibly a full quart or more.
BUT . . .
9. On the upside, your phosphate levels will remain low until you add fill water OR a phosphate based stain control agent. If you are careful, once the PO4 level in your pool is low, it will only take minimal time and expense to KEEP it low, unless you drain and refill your pool.
10. Once the PO4 is below 0.125 ppm, it will become MUCH easier to kill, and then prevent, algae.
Well, the good news is I'm pretty sure the iron is gone. Not only are there no stains, the stains on the white stairs are completely gone. I have a pump house and the plumber is coming tomorrow to reroute the fill source from the softener.
I did use some clarifier before I left town. Water looks pretty good, blue with algae debris on the bottom. Unable to filter as needs to go to waste. Will wait until tomorrow when I know source water is free of iron. Certain it will need to be done several times but can see bottom.
I ordered the phosphate test kit. I wouldn't be surprised to find them as there is a lot of farming where I am and this is some tough algae. Will test pool and fill water. Vacuuming to waste and replacing with good water, we may actually be able to use the pool next week. Plan to resolve any phosphate issues definitively before I close the pool this year.
Can't adequately express my gratitude to all of you for the guidance, support and concern :0)
I'd be grateful if you would post your results as you test your pool phosphates and other levels, and as you remover the phosphates. Remember to test your fill water, too. City water is usually the primary source of phosphates.
Also, I suspect that you will need LESS phosphate remover, if you make several moderate additions of phosphate remover, rather than trying to fix it in one dose.
Keep in mind that lowering phosphate is in ADDITION to chlorinating, and will have NO EFFECT on the algae, until your PO4 levels become lower than 0.25 ppm (250 ppb), and won't be fully effective till you have less than 0.1 ppm of PO4 present.
Thanks!
I was still getting mustard algae at 250ppb. It didn't stop until I got the pool under 125ppb.Quote:
Originally Posted by PoolDoc