Light green water

[PoolDoc]

I used to work with a CPO (Certified Pool Operator) that kept writing down a chlorine reading of 3.6 in the pool logs. I asked how he got that type of precision with the kit we were using (Taylor K-2005)when he tested our two commercial swimming pools where we worked.

Too funny . . . and nice detective work! I'm hoping to get my color-blind-vs-color-dumb page, complete with 'stories' posted this year!

[Huskerdee]

After much filtering and back washing my water is crystal clear; however, I have no chlorine levels. Should I add more of the calcium and metal remover before chlorinating? I have a lot of algaecide 60 in to prevent algae while I was awaiting my new test kit. I think all the back washing took my CYA way down. Anyway here are my readings.

Water temp - 69
PH - 7.3
Alk. - 200
CH - 400
CYA - undetectable
FC - 0
CC - 0
Saturation Index - 1.0

Oh yeah, my acid demand test was 2.

[PoolDoc]

No! Don't add any more of the Metal product (20% HEDP)

How did you get such high calcium levels? Is that much calcium present in your fill water?

You have a sand filter, right? If so the best way to run your pool might be with calcium hypochlorite and high stabilizer. I've been working a chemical guide page, and was very surprised to discover this AM that cal hypo can be purchased fairly economically at Amazon . . . if you know what to order.

The benefit, for you, is that doing it this way -- with a sand filter -- would allow you to continuously remove iron from your water. You'll end up with a manually dosed pool running with high calcium, moderate alkalinity, fairly high pH and high stabilizer. It won't be hard or expensive at all -- just a little different. If you get a K2006 (yeah, I'm still on that track!) you'll probably be able to work up to dosing just 1x per week, plus whenever you have to add water.

You could also use dichlor, and wouldn't have to add stabilizer manually. It will be more work to control the metals, whenever you have to add water, if you go that way.

MEANWHILE, add bleach in the evening, 1/2 gallon at a time to maintain your pool while you decide. But, the first time you add, add 1 whole gallon of 6% plain bleach, close to sunset. Test the water first thing in the morning, and again in the evening with OTO, not DPD. Let me know what you find.

[Huskerdee]

I did get and used a Taylor k-2006 test kit. That's what my last results came from. The calcium must be in our well water. Yes, I have a sand filter but thought Icouldn't use cal hypo because I have a vinyl liner? I have a SWCG but don't have it on yet. Should I just start that?

[PoolDoc]

Wow! That is truly bizarre, if the calcium is the well water. OK.

1. Cal hypo is fine in vinyl IF you don't drop it on the liner. (That's not why I want it in the skimmer, but adding it via the skimmer serves the purpose.)

2. You have the Intex SWCG w the copper? Can you disable the copper part? (Regardless: NO, don't start it yet. We need to get everything right, first.)

3. Please test your fill water, directly from whatever source you fill your pool. Please run it for at least 2 MINUTES before you collect a sample, so we're testing what ends up in the pool when you fill for awhile. (Ideally, collect your sample after you've been using water in the house, so the well pump has been running. But STILL run it for 2 minutes.)

[ Just had a thought: could you have rusting pipes putting the iron in the well water? It's just very, very unusual to have calcium and iron in the same well water. ]

4. If you can find a really clean white bucket, fill it with this water, after you collect a sample and then cover it with a towel, to keep dirt and sun out, but not air. Check it after 24 hours, to see what if anything has settled. And THEN test it.

(Don't run CYA test on any of these samples: it will use up your reagent, and you already know there's no CYA in that water. Unless you have a chlorine feed pump, you don't need to check chlorine in the well samples.)

[Huskerdee]

I have a doctor appointment in the city tomorrow. I will stop and get cal hypo and do the testing of hydrant water when I get back.

[PoolDoc]

about 1/3 lb in the skimmer at a time. You must be 100% sure no other chemicals are in the skimmer, or anywhere between the skimmer and the filter. The pump must be on, and remain on for at least 30 minutes after.