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my_youngminds
10-23-2012, 09:29 AM
I am struggling with trying to battle an alage problem for a few months now (since the end of summer). I just can't seem to get ahead of it and am not excited about dumping more $$$ into pool chemicals. Sad to say, I kind of just gave up and haven't done anything but vacuum the past week or so. I went out this morning and took readings and here are the results:
FC:0
PH: 6.8
TA: between 0 - 40
TH:0
CYA: between 0 - 30

I did fill out the form, but not sure how that gets attached to my signature. So, I have a 30 ft. round, above ground pool. A Proline high rate, 22 inch diameter sand filter with a Proline 1.5 HP pump. This morning I did go out and added 12 lbs. of baking soda to raise the PH (I hope that was the right thing to do.). I do have about 10 1.5 gallons of bleach ready to go. I would really appreciate if someone could give me a detailed plan on how to get my pool cleaned up. In the meantime, I will continue to vacuum it. Thank you very much. I also have pictures, but not sure how to attach them. I'll try dragging it onto this post to see if it works. Thanks.

/Users/Sean/Pictures/iPhoto Library_2/Masters/2012/10/23/20121023-091737/PA223346.JPG

aylad
10-24-2012, 07:30 AM
Hi, and welcome to the forum!

First off, how are you testing? I suspect you're using strips, which are not really reliable and not accurate enough to clean up a mess. The reason that's important is that in order to kill the algae, you need to raise your chlorine level to "shock" level, and how high that is will depend on your CYA. So....if your CYA is actually 30 ppm, then you need to raise your chlorine to at least 15 ppm and hold it there. If your CYA is 20 or less, then you need to get your chlorine to 12 ppm and maintain that. WalMart sells a 6-way drop kit by hth that would work for now--it runs around $20. My WalMart still has some, but you'll have to check and see if they're available in your area.

So,...the first thing you need to do is fix your pH, since pH readings are not accurate with chlorine levels above 10 ppm or so. Use 20-Mule Team Borax to raise your pH instead of baking soda--baking soda will raise your TA, but you don't need to worry about that. Your TA will come up some when you get the pH up where it needs to be, which is in the 7.0-7.8 range. Anything below 7.0 is acidic and can damage your liner. And most tests don't read pH lower than 6.8, so your 6.8 could actually mean "6.8 or LOWER". It might take quite a bit of Borax to raise it, but you'll have to dose a little at a time and see how it goes. I would start with about 1/2 box, poured very slowly into the skimmer, breaking up clumps. Give it a couple of hours to distribute, then test and add more if necessary until you see your pH rising.


Once you get the pH fixed, then you need to raise your chlorine levels to the shock level I talked about earlier. If you can tell me the height of the water level in your pool I can figure your volume, but if you know it, that would help too--once I know that I can give you some guidelines on the amount of bleach to add. Once you attain shock level, you need to maintain it as consistently as possible by testing and adding more chlorine as necessary to keep it high...the more consistent you are about this, the faster the pool will clear.

Keep the pump running 24/7, backwashing the filter when the pressure rises by 6 psi or so (this will probably be pretty frequent during the cleanup), and brush the pool daily, preferably after a bleach addition to loosen as much algae as you can.

It will take some patience and alot of bleach, but it will clear!

my_youngminds
10-24-2012, 02:55 PM
Thank you so much for the helpful advice! I did a little more reading while awaiting advice here and started dumping the bleach in last night after using the handy pool calculator. I am AMAZED at the difference just overnight and even more so this afternoon. I am, unfortunately, using the test strips right now, but do have the drop kit on order. Our pool is about 23,000 gallons. I will have to get some more borax to maintain the pH, I'm sure. My pH this morning was 8.4 and the FC was 10. I added 2 more gallons of bleach this morning. When we got home this afternoon I was shocked at the difference in the water. It is not looking like "primordial soup" anymore! It is a light, cloudy green. The FC dropped to 5, so added about 3 more gallons of bleach. The pH was at 7.8. Do I need to do something to get the CYA up? Thank you again for your help!

Jennifer

my_youngminds
10-25-2012, 12:21 PM
Update: I think we are well on our way. It's looking better each time I go out. FC was back down to 5 this morning, so dumped in a bunch more bleach, per the pool calculator suggestions. The Ph is 7.5, TA: 80, CYA: 30-50. I also got my test kits delivered this afternoon and can I start by saying..."Oh my...feels like overkill and am totally overwhelmed from just opening the kit!" I got the Taylor K-1000 and Taylor K-2006c kits. I thought I remember reading somewhere that there were videos somewhere on how to use these kits. For now though...to get the pool ready to close, any suggestions on how to quickly learn the parts of the kit that I need to know?

Also, speaking of closing, does anyone have experience without using a cover. We are in a very high wind area and am very exasperated about the money we put into a winter cover every year because they don't last one season. We've used clips, jugs, plastic wrap...you name it... We were wondering what the effects would be if we did not cover. Or maybe just using one of those mesh covers to catch larger debris?

Thank you again for your help.

Jennifer

my_youngminds
10-25-2012, 04:12 PM
Update to my update: Sorry if I am too pesky. :) I did test the chlorine, pH and CYA of my water using the Taylor kit. Here are the results (I can't believe the difference in the drops vs. the strips.):
FC: 20.5
CC: 1.5
pH: 8
CYA: 0 (My mixture wasn't cloudy at all...is that a problem.)

my_youngminds
10-26-2012, 08:25 AM
My pool is at the cloudy, blue stage and has been there since yesterday. What would be my next step in getting it clear?

BigDave
10-26-2012, 12:02 PM
Congrats on figuring out the tests in the K-2006! - it's intimidating when you see the kit for the first time but it's really easy once you work through each test once or twice. Your experience is yet another example of why we don't trust test strips - they are unreliable and usually inaccurate.

I'd like to draw your attention to two links in aylads signature above (note: you'll need to log out to follow them) the first is the Best Guess Chlorine Chart and the other is Using muriatic acid to lower your pH. Don't try to lower your pH now as it is probably reading falsely high because of your high chlorine.

Your FC of 20.5 is a bit high for a CYA of 0 but you are killing / cleaning algae. I'd let it drop a little and keep it between 10 and 15 'til your water is cleared. Follow Janet's advice about maintaining chlorine level, running and cleaning the filter, and brushing the pool.

When the pool is clear and CC is < 0.5ppm, you can perform an overnight chlorine test to verify that the algae is beaten. Test chlorine in the evening near sunset and again early in the in the morning near dawn. If you lose less than 1ppm FC overnight, you're done with the algae. If you lose more than 1ppm overnight, keep up the cleanup process (Bleach, Brush, Backflush as necessary) until you can pass the overnight test.

When the algae's beaten, add CYA, let the FC drift down to normal, and adjust the pH. Then close a clean pool.

my_youngminds
10-26-2012, 08:50 PM
Well, I thought I might have gotten all of the algae, but from my readings today maybe not? Can someone tell me what they think and what my next step should be?

9am reading:
FC: 18.5
CC: 0
pH: 8.0

Did a backwash and ran the Rover pool vac continuously throughout the day.

3pm did another backwash.

6pm reading:
FC: 7.5! (Isn't that quite a drop? Especially since the weather is cloudy and rainy?)
CC: 0 (which kind of had me confused. Doesn't CC mean something is growing?)
pH: 7.4
Added 2 (182 oz. jugs) of 6% bleach, per the pool calculator's calculations to raise FC back up to 15.

8pm
FC: 16.5
CC: .5
pH: 8.2

Guess I'll see how much it drops overnight, correct? As that will tell me if I'm losing chlorine to something growing or the UV from the sun? Is that correct thinking? The water is a very "pretty" (as opposed to primordial soup green) milky, bluish color. I cannot see the bottom yet. At some point should I stop the filter to let the suspended stuff settle so it can be vacuumed to waste? Sorry for all of the posts. I feel like I am so close, but if I don't keep on top of it or do what needs to be done next, then I will lose control of it again. And I really don't want all of my $$ and time going to waste again. Thank you for any replies.

Watermom
10-27-2012, 02:28 PM
You are thinking correctly in regards to the chlorine loss. The reason you are losing so much chlorine during the day is because of your CYA reading of 0. So, that can't tell us if you are still fighting something in the water. Only a chlorine loss overnight can give us that information.

It takes awhile to filter out dead algae especially when you have a larger than needed pump on an AG pool. In the case of pool pumps, bigger is NOT better. A too powerful pump forces debris through the sand bed instead of filtering it out very well.

BigDave
10-27-2012, 02:31 PM
Filtration is what's going to remove the cloudy. Is your filter pressure rising?

With 0 CYA, you are going to lose alot of chlorine to sunlight - cloudy or not.

BigDave
10-27-2012, 02:32 PM
Watermom and I were posting at the same time - Sorry mom. Same advice though.

my_youngminds
10-29-2012, 09:42 AM
Well, I think I have the algae beaten. It only dropped 1ppm for 2 nights. However, now we have Hurricane Sandy and I had to turn the pump off during this storm. I foresee it being off for at least 3 days. Last I checked (yesterday morning) the FC was at 17 and pH was at 7.7. Any suggestions on what I should expect or will probably need to do after the rain? Also, while it's raining I was reading up on increasing CYA and getting what I needed to do that and was a little overwhelmed with what I was reading here. Do I need to wait for my pool to be clear or just the algae beaten (but water still cloudy) to increase the CYA? Also, the small jar at the pool store was $$$$. It was $20 for 5 lbs! Is there a source/brand that you recommend? Thank you for your advice. It's been a tremendous help!

PoolDoc
10-30-2012, 06:23 AM
membership updated.

Maintaining adequate chlorine (> 2.0 ppm where CYA = 0) should prevent the algae from regrowing. You can do this with 6% plain household bleach. Note that chlorine levels will drop RAPIDLY, once post-storm clear skies arrive, so add daily bleach doses late in the evening to allow them to work all night before being destroyed by sunlight.

my_youngminds
10-31-2012, 01:32 PM
well, not sure what to do. We are currently without power and isn't anticipated to be back on until Monday. I checked the chlorine level this morning and the FC was 1, CC was .4 and pH was 7.3. Is it ok to walk along the edge of the pool and dump some bleach in, if it's not being circulated? On a positive not, the dead algae settled and I can see the bottom and the water is clear. So when we get power back I can give it a good vacuum to waste. Just trying to figure out what to do until we can get our pump running again. Thank you again for the suggestions.

Charlie_R
11-03-2012, 08:32 AM
If you haven't already figured it out, yes, you can pour bleach in around the edges, and stir the water with your brush/broom.

waterbear
11-04-2012, 11:47 AM
9am reading:
FC: 18.5
CC: 0
pH: 8.0

Did a backwash and ran the Rover pool vac continuously throughout the day.

3pm did another backwash.

6pm reading:
FC: 7.5! (Isn't that quite a drop? Especially since the weather is cloudy and rainy?)
CC: 0 (which kind of had me confused. Doesn't CC mean something is growing?)
pH: 7.4
Added 2 (182 oz. jugs) of 6% bleach, per the pool calculator's calculations to raise FC back up to 15.

8pm
FC: 16.5
CC: .5
pH: 8.2



This is a GREAT illustration of how high FC levels can cause a false high pH reading! There is a chemical reason for this but the chemistry is somewhat complex so I will spare you the details. Just be aware that pH readings are suspect when the FC is above 10 ppm (but still 'usable, if not totally accurate up to about 15 ppm since the error is not that great).