Never Ending Green Algae

[GypsmJim]

I'm starting a new thread so nobody has to read thru all of the old trials and tribulations...

To summarize:
Had a pool for 25 years and never had algae problems before. The third time it happened this year I found this site. Bought the recommended kit, did the slam, etc, etc. Switched to grocery store high strength bleach. The pool was crystal clear for more than a week, but now its back.

The slam was by YOUR procedure. Had the FC wayyy above the slam target. The FC went down 0 or 1 for 5 days straight. One day it even went up one. Then I let the FC drop. It took almost 2 weeks to drop to the target. Then I started using store bleach and maintained it at target every single day.

Friday I noticed a hint of cloudyness, but no green. We went away for the weekend so Sat morning I added what I figured would be 3 days of bleach and a little clarifier. Sure enough we come back Mon and the FC is still OK, but the pool turned green.

Tests are:
FC = 7
CYA = 60
Cc = 0
pH = 7.5
TA = 100

Obviously, I'm doing something wrong. Where do I look next?

 

[pabeader]

I see you have your FC at 7, which is the target for your CYA level. I would wonder if you have been able to keep it at that all the time? What is your daily loss? How much extra did you put in, in anticipation of the time away?

Clarifier? What product name?

 

[Catanzaro]

I'm starting a new thread so nobody has to read thru all of the old trials and tribulations...

The slam was by YOUR procedure. Had the FC wayyy above the slam target. The FC went down 0 or 1 for 5 days straight. One day it even went up one. Then I let the FC drop. It took almost 2 weeks to drop to the target. Then I started using store bleach and maintained it at target every single day. Friday I noticed a hint of cloudyness, but no green. We went away for the weekend so Sat morning I added what I figured would be 3 days of bleach and a little clarifier. Sure enough we come back Mon and the FC is still OK, but the pool turned green.

Tests are:
FC = 7
CYA = 60
Cc = 0
pH = 7.5
TA = 100

Obviously, I'm doing something wrong. Where do I look next?

Please do not use any clarifiers. Your pool is "green"? Is this algae? Can you brush up the algae off the walls, floors and steps? And does it break up in the water? Only use liquid bleach and nothing else.

If algae, then another SLAM may be in store for you, but please keep track of the process and post all results. No decrease in FC or a small amount does not sound like it is algae and your CC is not reflecting any problems.

Which test kit are you using? Can you post some pictures? Please add your signature, including all your equipment, etc. Thanks !

 

[GypsmJim]

The FC had been running 8-9. I check it every single evening after sundown. The daily loss was 1. I purposely kept it above target in view of the past problems. I had been putting in a pint of 8.25% bleach every day and it never went below 8. Since I would miss sat and sun treatments I put in 3 pints, in other words an extra one for good measure. By past weeks performance today's reading should have still been good (and it was at 7), bit it was green.

The clarifier was the last few ounces in the bottle and I threw it away so I don't know. Clear bottle, blue liquid...been using it for years.

 

[GypsmJim]

Please do not use any clarifiers. Your pool is "green"? Is this algae? Can you brush up the algae off the walls, floors and steps? And does it break up in the water? Only use liquid bleach and nothing else.

If algae, then another SLAM may be in store for you, but please keep track of the process and post all results. No decrease in FC or a small amount does not sound like it is algae and your CC is not reflecting any problems.


Which test kit are you using? Can you post some pictures? Please add your signature, including all your equipment, etc. Thanks !

TF100 test kit. The water is green throughout, with some settlement on the bottom (green dust). Nothing on the sides.

24' round pool, vinyl, 1.5 HP sand filter. Its dark now and work tomorrow so pics and sig will have to wait.

 

[Catanzaro]

Is there a pool store near you to test for Metals? If algae, then a SLAM is needed. At 1 ppm loss daily, it does not sound bad. I average about 1.9 daily, (averaged weekly), and there is little activity. So most of the loss is from the Sun. Are you in full sun? Maybe the clarifier, which sounds like an algae preventer contained metals, which could have caused this problem. Hard to tell. Your test results do not show issues.

Is this an above ground pool? Or in ground? How deep? If your levels have been on track, it is very possible you have a circulation problem, and/or a filtration issue. I help a friend and our levels have never ever dropped, but in real hot weather, he started seeing algae spots here and there. This is due to poor circulation and lack of brushing walls, etc. Only has one return, one skimmer and one main drain for a 20,000 gallon pool. Mine is smaller and I am working with 8 returns, 2 main drains and 2 skimmers, which in turn keep circulation in check.

Maybe post pictures of pool, equipment, ladders, steps, etc. How many hours do you run the filter?

More information, we can get to the bottom of this issue. Third time this year sounds like something else may be going on.

 

[duraleigh]

GJ,

Algae cannot grow in a pool that is adequately chlorinated......period. So, if you have algae, your pool was not adequately chlorinated. It is very difficult to get around that simple fact.

If you have iron precipitation, which I doubt, that is a completely different issue that can almost always be put to rest with a good pic of your pool water.

Post up that pic, we'll help decide if you have metals (I doubt it) and then we'll get to work figuring out how your chlorine got so low as to allow algae.

 

[GypsmJim]

Is there a pool store near you to test for Metals? If algae, then a SLAM is needed. At 1 ppm loss daily, it does not sound bad. I average about 1.9 daily, (averaged weekly), and there is little activity. So most of the loss is from the Sun. Are you in full sun? Maybe the clarifier, which sounds like an algae preventer contained metals, which could have caused this problem. Hard to tell. Your test results do not show issues.

Is this an above ground pool? Or in ground? How deep? If your levels have been on track, it is very possible you have a circulation problem, and/or a filtration issue. I help a friend and our levels have never ever dropped, but in real hot weather, he started seeing algae spots here and there. This is due to poor circulation and lack of brushing walls, etc. Only has one return, one skimmer and one main drain for a 20,000 gallon pool. Mine is smaller and I am working with 8 returns, 2 main drains and 2 skimmers, which in turn keep circulation in check.

Maybe post pictures of pool, equipment, ladders, steps, etc. How many hours do you run the filter?

More information, we can get to the bottom of this issue. Third time this year sounds like something else may be going on.

Above ground, 24'x52". The filter runs 7 to 10 am and 7 to 10 pm. Full sun most of the day. The water temp had dropped to about 72 (it was crystal clear then) but has now risen to 82 with the past week of hot weather. I added the clarifier because I detected cloudiness, which was always the start of green before. So, actually, the issue started before the clarifier was added.

I added 3 gal of bleach last night, and now this morning the green is gone, but still cloudy. There is settlement on the bottom of "dirt", but not really too bad. There is 1 skimmer and 1 return. The return is directed downward and the pool has a good circular motion when the pump is running. I don't know if the circulation is adequate or not, but I can say that when debris is present (broken bits of leaves, bugs, etc.) it always collects on the bottom in the middle.

- - - Updated - - -

GJ,

Algae cannot grow in a pool that is adequately chlorinated......period. So, if you have algae, your pool was not adequately chlorinated. It is very difficult to get around that simple fact.

If you have iron precipitation, which I doubt, that is a completely different issue that can almost always be put to rest with a good pic of your pool water.

Post up that pic, we'll help decide if you have metals (I doubt it) and then we'll get to work figuring out how your chlorine got so low as to allow algae.

The CYA is 60 and last night the FC was 7. That's testing with your recommended kit.

The last slam was several weeks ago and it was maintained at about 50 until the overnight change was less than 1. So, 50+ for 5 days. Since then it has drifted downward slowly. 7 was the lowest # in weeks. I test it every day in the evening.

That's the data. Is 7 "so low"?

- - - Updated - - -

PS - if the cl made the green disappear over night doesn't that rule out heavy metals?

 

[Catanzaro]

Keep your filter running 24/7 until the SLAM is done. Brush walls and floors often to keep algae in check.

Based on a CYA of 60, your minimum is 5 and your target is 7. This assumes you loose about 2 ppm daily. If you have heavy activity, then you could loose between 4-5 daily (add accordingly). Maybe increase filtering time to 10 hours, then back to 8, then to 6 (experiment a little bit).

 

[duraleigh]

I added 3 gal of bleach last night, and now this morning the green is gone, but still cloudy.

Adding a one-time dose of 3 gallons does very little. Despite everything you have done in the past, you have algae and the correct way to eliminate that is to SLAM the pool.

Checking the Chlorine/CYA chart in Pool School, your CYA of 60 requires an FC value of 24 ppm.....not 50+ ppm where did you get that?

That 24 ppm must be help until your pool is crystal clear. The SLAM process cannot be conformed to something else....follow the instructions to a T.

 

[GypsmJim]

Adding a one-time dose of 3 gallons does very little. Despite everything you have done in the past, you have algae and the correct way to eliminate that is to SLAM the pool.

Checking the Chlorine/CYA chart in Pool School, your CYA of 60 requires an FC value of 24 ppm.....not 50+ ppm where did you get that?

That 24 ppm must be help until your pool is crystal clear. The SLAM process cannot be conformed to something else....follow the instructions to a T.

It was a T. This was my criteria:

You are done when:

• CC is 0.5 or lower;
• You pass an OCLT (ie overnight FC loss test shows a loss of 1.0 ppm or less);
• And the water is clear.

When that happened, I let the FC drop. I just dumped in some CL in the begining and the 50+ is where it rose to. I didn't pick that number, but since it was above the 24 req'd I figured it was OK. More is Better? If 24 kills it, would 50 be OK?

It was late last night and 3 gal was all I had. I WILL follow the procedure again starting tonight.

 

[duraleigh]

If 24 kills it, would 50 be OK?

Dosages are there for a purpose. It seems apparent, you didn't dose but just tossed in some FC. I won't get into semantics but dumping in 50+ FC is not following the SLAM process to a T. If taking 2 aspirins cures your headache, does taking four aspirin cure it even better?

I want to reemphasize my first post......algae will not grow in an adequately chlorinated pool. Your pool has water just like the water in my pool and your algae is likely the same as the algae I get. I have no idea how to continue to help........what you are doing works for thousands of others on a consistent basis. Why it doesn't work for you is beyond the scope of my knowledge.

 

[GypsmJim]

Dosages are there for a purpose. It seems apparent, you didn't dose but just tossed in some FC. I won't get into semantics but dumping in 50+ FC is not following the SLAM process to a T. If taking 2 aspirins cures your headache, does taking four aspirin cure it even better?

I want to reemphasize my first post......algae will not grow in an adequately chlorinated pool. Your pool has water just like the water in my pool and your algae is likely the same as the algae I get. I have no idea how to continue to help........what you are doing works for thousands of others on a consistent basis. Why it doesn't work for you is beyond the scope of my knowledge.

The start of my slam, getting the test kit and following the directions didn't all happen at once. I found this site after the initial Cl addition. If I knew the 24 at first I wouldn't have added that much. When I added the cl I couldn't test. Since one addition didn't do anything I kept adding until the green went away. Once I got the test kit I then knew it was 50. At that point I didn't add any more. I continued to monitor the fc daily and thus watched it go back down.

OK, I understand that I could hurt the liner with high cl, and if I did that's another issue. What I'm trying to figure out is why the algae didn't clear up when it was shocked that high, and moreover, since I'm now in a position to properly test, why has it come back even though the fc never went below the target.

 

[kimkats]

Jim, Have you taken the steps out? Do you have a light? Have you looked all around and inside the skimmer and return?

You have algae hiding somewhere. I have a thread for you to see. He did a graph (post #58) and it shows right where he found the algae in his light. Once he got that clean he was able to finish his SLAM.

Think it's time to take back my pool... - Page 3

Good luck. Keep up the SLAM using your test kit and you will be able to float along just fine!

Kim

 

[GypsmJim]

Jim, Have you taken the steps out? Do you have a light? Have you looked all around and inside the skimmer and return?

You have algae hiding somewhere. I have a thread for you to see. He did a graph (post #58) and it shows right where he found the algae in his light. Once he got that clean he was able to finish his SLAM.

Think it's time to take back my pool... - Page 3

Good luck. Keep up the SLAM using your test kit and you will be able to float along just fine!

Kim

I have made a thorough inspection. All of the contaminants are dust like and settle to the bottom. There is nothing on the side walls, or even the steps. I also made the graph you cited to chart the performance, and that told me when the slam was finished last time.

For the third time last night I readjusted the return ball. Looks like I may have a better circulation now. This morning all the green water color was gone (just a little cloudy) and the only settlement was right in the center on the bottom. I'll vacuum to waste again tonight.

Last night's fc was just 2 points below slam level, so I added more cl. After the last slam the water was crystal clear, no settlement, etc. Every time I vacuumed I ran to waste. The settlement didn't reappear until the fc dropped to 9.

Thanks for the help...

 

[PAGirl]

How often do you brush the pool? That important step is often overlooked.

Have done an OCLT lately?

 

[GypsmJim]

How often do you brush the pool? That important step is often overlooked.

Have done an OCLT lately?

Its brushed daily and vacuumed about twice a week. Sometimes to waste, sometimes to the filter.

The OCLT showed 0-1 up until a few days ago when the green came back (after I was gone for 3 days). I haven't checked it again since the fc was raised.

 

[GypsmJim]

I thought I would give an update and maybe get suggestions for next year. After the third slam the algae started coming back again, which was the subject of this post in the first place. The formation again was dust like and only in the center. The pool is now 1/4 drained and covered for the Winter.

The slam was supposed to go to FC = 24. I got it as high 34 by adding too much store bought 8% bleach. I then let it go down by itself after all 3 criteria were met. The last week showed 0 ocld EVERY day. The 24 hour drop was sometimes 0, sometimes 1 and twice it went up 1. The water was crystal clear. We had a lot of rain 1 day and had to put the sand filter to waste 1 night and had a malfunction. The filter valve had been getting hard to turn and that night it got stuck on waste. It would not go back to filter. A quick trip to the pool store to get a new valve and all worked well after that. 2 days later the pool was put to bed.

Could the filter have been malfunctioning all the time? When i drained the sand filter I got a little green out the bottom and the top showed a normal amount of solids. The sand was about 1/3 gone, which is lower than I remember when it was opened in the Spring. The ladder and all stuff were removed and all showed 100% clean, so there was no alage hiding anywhere.

Should I add more sand in the Spring, or should I add DE like I've been reading about?

 

[PAGirl]

When you leave, does anyone maintain your FC for you? It doesn't seem to take much to see green if the level falls below the minimum. (Ask me how i know, ha ha.)

You would want to add sand to the proper amount, then add the DE. If the filter wasn't moving the water properly, that could lead to circulation problems. Hopefully you have a better season next year!

 

[kimkats]

Like PA girl says--add proper amount of sand when the time comes. DE is just a "back up" in a sand filter to give it a helping hand when needed. It is NOT to replace the sand.

Kim