Help with test results and cloudy water

[superjet]

I have my first problem with my chemistry. I ordered the test kit a few weeks ago, but haven't received it, so I'm still relying on an old kit and pool store tests. Here are the last 4 pool store test results from their drop kit:

6/5
FC 0
CYA 0
ph 6.8
Alk 120
Salt 3000
TDS otc

5/27
FC .1
CYA 80
ph 7.4
Alk 110
Salt 3000
TDS otc

5/9
FC .2
CYA 80
ph 7.5
Alk 100
Salt 4000
TDS otc

5/4
FC .2
CYA 80
ph 7.6
Alk 100
Salt 0
TDS 1250

* otc = off the chart

I think my salt generator is failing so I loaded my skimmer with 4 pucks before going away for 4 days. I came back to my cover being loaded with algae filled water due to rain and 90+ degree temperatures. Drained the cover and opened to find blue cloudy water. I have poured in 5 gallons of bleach and kept a couple of pucks in the floater for the last 36 hours. I backwashed my filter and vacuumed to waste yesterday. Doing that drained a couple of inches, so I refilled with city water.

What caused my CYA to disappear? How do I get my water back to normal?

Greg

[aylad]

The only two reasons for the CYA discrepancy are 1)incorrect testing, and 2)swampy green water. Severe algae outbreaks do have a tendency to break down the CYA, so if the algae bloom happened in that 2 weeks between 5/27 and 6/5, that could have been the culprit. You can add CYA in your skimmer, or in a sock in front of a return, and give it 1 week or so to dissolve. To clear up your water, you need to dose it with bleach to get it up to 10-12 ppm and keep it there by daily additions until the green is gone and the filter clears the water.

Your most important task, though, is to get the pucks in the floaters out of your pool and raise your pH using Borax before you have damage. 7.0 should be your minimum pH.

Janet

[Poconos]

Greg,
I have done this in the past when I needed to jack up CYA pretty fast. Since you have pucks already you can crush them. They pulverize very easily. I put one on a couple sheets of newspaper on a cement floor, cover with another couple sheets and gently hit with a 3# hand sledge. Hardly have to hit them to break them up. Then I chuck the powder in the skimmer and let the powder dissolve in the filter. Dissolves fast. I have a sand filter but have to say I don't know if you can get away with this with DE or cartridge. You get the added benefit of adding chlorine at the same time but watch your pH. It will drop.
Al

[waterbear]

CYA won't disappear that fast (in just over a week) unless you have drained and refilled or unless you have added a LOT of melamine (cya reducer, expensive, wastefull stuff) to the pool. Biodegradation by anerobic bacteria is a slow process and I really don't think it can reduce you from 80 ppm to 0 in that short a time. I vote for bad testing! Also the drop in pH with the rise in ALK on the last test looks suspicious to me.
TDS is a pretty much usless test and in a salt pool is alway going to be higher than your salt level which is a big part of the TDS!
Get the water retested. Or better yet get the $15 walmart kit that tests for CYA and test it yourself!
Your numbes show that the algae has possibly created a chlorine demand in your pool. That is why the FC is not holding. Do you have any numbers for TC? If the genterator is not producing enough chlorine then you probably had the start of algae and that was causing your FC to be low. Also the tests showed no salt on 5/4, 4000 ppm on 5/9 and then 3000 ppm on the next two. Unless you really had no salt and added a lot and then drained some of your water to get it down those readings are bogus. If you are relying on the readout on your SWG those readings could very well indicate the cell is failing. If they came from testing at the pool store their test practices are not very good.
Just my 2 cents.

[waste]

Al, great idea! It should work in any type filter, as long as it's not backwashed out too soon. As a suggestion, if you don't want to go 'ballistic' with the 3#, pound it down to 'small chunks and dust' and put it in a sock (as per Janet) or a section of pantyhose or kneehigh and tie it off and drop it in the skimmer. I am doing this with the cya granuals and the dissolution rate is much quicker than just dumping it onto the pool bottom (and you don't have to worry about backwashing with it still in the filter, nor the sight of a couple #s of cya sitting on the bottom of the pool)

[superjet]

CYA won't disappear that fast (in just over a week) unless you have drained and refilled or unless you have added a LOT of melamine (cya reducer, expensive, wastefull stuff) to the pool. Biodegradation by anerobic bacteria is a slow process and I really don't think it can reduce you from 80 ppm to 0 in that short a time. I vote for bad testing! Also the drop in pH with the rise in ALK on the last test looks suspicious to me.
TDS is a pretty much usless test and in a salt pool is alway going to be higher than your salt level which is a big part of the TDS!
Get the water retested. Or better yet get the $15 walmart kit that tests for CYA and test it yourself!
Your numbes show that the algae has possibly created a chlorine demand in your pool. That is why the FC is not holding. Do you have any numbers for TC? If the genterator is not producing enough chlorine then you probably had the start of algae and that was causing your FC to be low. Also the tests showed no salt on 5/4, 4000 ppm on 5/9 and then 3000 ppm on the next two. Unless you really had no salt and added a lot and then drained some of your water to get it down those readings are bogus. If you are relying on the readout on your SWG those readings could very well indicate the cell is failing. If they came from testing at the pool store their test practices are not very good.
Just my 2 cents.

I did add 300# of salt to get the salt up when I opened the pool. That explains the shift in salt....sorry for not posting that detail. I have backwashed twice and vac'd to waste once since then, so I've added some water, but at most at few inches lost and readded.

BTW...The pool has a nice green tint to it today. I hit it hard with chlorine tonight. Should I try to raise my ph with Borax? Should I hit it with polyquat?

[waterbear]

I would keep hitting it with chlorine until you kill the algae. And I would retest the CYA. I really think the 0 reading you got was bogus. I am also a bit suspcious of the pH results in that test too. Retest that also although it could be the result of the pucks.

[superjet]

Thanks for all the help!

[superjet]

I checked the ph with my kit and it is 6.8. Should I attempt to raise it with Borax? The pool is clearer (but still cloudy) this morning, so I will keep the cl up and have my son brush and vac today.

[Watermom]

Yes. Need to get the ph reading above 7.0 asap. Readings below that are acidic and can damage your pool.