Do I need to kill algae before treating for high phosphates

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Snowshoe

Snowshoe

Well-known member
Jul 23, 2021
50
San Jose CA
Pool Size
22000
Surface
Plaster
Chlorine
Liquid Chlorine
Ok I screwed up. I've been having algae problems for months. We get a lot of leaves and junk blowing into the water, especially in the winter, and although I am good about skimming it out daily with a net I now have a very high phosphate level. Although I have kept my chlorine, pH and alkalinity levels balanced my Taylor test kit does not have a test for phosphates and I didn't take a sample into my local chain pool store because (insert lame excuse here). I had it tested today and the test came out at over 3800 ppb. As a typical chain store they want to sell you as many chemicals as they can and they had 4 chemicals on their list I should use to kill the algae before I even start to treat for the high phosphates.

So my question is do I really need to try and kill the algae before treating (sucking out) the phosphates or can I do the phosphate treatment and then shock the pool to kill the algae? If I should treat for algae prior to the phosphate treatment do you have suggestions as to what to use that doesn't involve 4 different products?

Your expertise and suggestions are much appreciated.

Charles
 
Snowshoe said:
Ok I screwed up. I've been having algae problems for months. We get a lot of leaves and junk blowing into the water, especially in the winter, and although I am good about skimming it out daily with a net I now have a very high phosphate level. Although I have kept my chlorine, pH and alkalinity levels balanced my Taylor test kit does not have a test for phosphates and I didn't take a sample into my local chain pool store because (insert lame excuse here). I had it tested today and the test came out at over 3800 ppb. As a typical chain store they want to sell you as many chemicals as they can and they had 4 chemicals on their list I should use to kill the algae before I even start to treat for the high phosphates.

So my question is do I really need to try and kill the algae before treating (sucking out) the phosphates or can I do the phosphate treatment and then shock the pool to kill the algae? If I should treat for algae prior to the phosphate treatment do you have suggestions as to what to use that doesn't involve 4 different products?

Your expertise and suggestions are much appreciated.

Charles
Click to expand...
Also if you can recommend any specific phosphate treatment products (or ones to avoid) that would also be helpful.
 
The SLAM Process doesnt use phos removers.

It's a process. Read it, digest some, read it twice more. Follow it to a T and you'll be TFP clear in a short time. It didn't become a swamp overnight and it won't be cleared as quickly either.

Fire off any questions along the way and we'll help. :)
 
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Generally, this forum doesn't worry about phosphates. If your FC is where it needs to be, phosphates arent a problem because you will have no algae.

Looks like youll need to slam to get rid of the algae.

Post a full set of test results.
 
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The prescription for algae is the
SLAM Process with liquid chlorine.
Regardless of the presence of phosphates.
So slam first then treat for phosphates later after eradicating the algae if you’re still worried about them (hint- we’re generally not).
Here’s some info about phosphates & their removers

Phosphate Removers - Further Reading

www.troublefreepool.com www.troublefreepool.com
 
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Snowshoe said:
Ok I screwed up. I've been having algae problems for months. We get a lot of leaves and junk blowing into the water, especially in the winter, and although I am good about skimming it out daily with a net I now have a very high phosphate level. Although I have kept my chlorine, pH and alkalinity levels balanced my Taylor test kit does not have a test for phosphates and I didn't take a sample into my local chain pool store because (insert lame excuse here). I had it tested today and the test came out at over 3800 ppb. As a typical chain store they want to sell you as many chemicals as they can and they had 4 chemicals on their list I should use to kill the algae before I even start to treat for the high phosphates.

So my question is do I really need to try and kill the algae before treating (sucking out) the phosphates or can I do the phosphate treatment and then shock the pool to kill the algae? If I should treat for algae prior to the phosphate treatment do you have suggestions as to what to use that doesn't involve 4 different products?

Your expertise and suggestions are much appreciated.

Charles
Click to expand...
Welcome to TFP, I grew up in San Jose. Following TFP, you don’t need to worry about phosphates. If you have algae, you just need Chlorine. Read up on the SLAM process above and ask any questions as they come up.
 
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Thanks to everyone's expertise. I knew I would get the real poop here as I did a few years ago when I discovered the pool at this rental house had been using dichlor tablets for many years if not decades and I found the CYA off the charts and I ended up close to emptying the pool.

My D.E. filter is due for a flush and I found when I moved in here that back washing does a terrible job at cleaning the elements (the DE cakes on the elements and does not completely wash off with a back wash) so I take all the elements out and hose them down which is a job I'm not fond of at all so I will not start the SLAM until this weekend. I've been away for 2 weeks and although my wife has been adding chlorine while I was gone the algae was not good when I got home so my plan is to brush the algae the next couple of days and get as much of it sucked into the filter as possible before I clean the filter and then start the SLAM.

So I have one more question: My FC is about 8 right now and I have about 35 pounds of dichlor tablets left over from a couple of years ago before I switched to liquid but on the SLAM page they say "It is especially important to avoid using dichlor when SLAMing, as it will raise CYA far too quickly." I don't agree with this. It can't raise the CYA THAT quickly as everyone using the tablets would have CYA off the charts and be in a world of hurt (my current CYA is about 60). IMHO it takes a couple/few years if not longer of using them before they cause trouble. I'm thinking that ONLY BEFORE I start the SLAM I start raising the FC level using the tablets - I have 3 floaters I could use - so that I maight be able to get the FC level I need to start the SLAM (which is 24 ppm) - at which point I would pull the dichlor out and would then only use liquid CL. Opinions?
 
Snowshoe said:
I don't agree with this.
Click to expand...
With a CYA of 60, you are already in the harder to slam zone. Going (semi-)full @Donldson, DO NOT USE TABLETS. Use liquid chlorine. Full stop, do not pass go, do not collect $200 use liquid chlorine.

LIQUID CHLORINE.

Follow the process it works. Proof? Link-->How Clear is TFP Clear?

Ok, not quite full @Donldson, but getting closer. 🤣
 
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Snowshoe said:
"It is especially important to avoid using dichlor when SLAMing, as it will raise CYA far too quickly." I don't agree with this. It can't raise the CYA THAT quickly as everyone using the tablets would have CYA off the charts and be in a world of hurt (my current CYA is about 60). IMHO it takes a couple/few years if not longer of using them before they cause trouble. I'm thinking that ONLY BEFORE I start the SLAM I start raising the FC level using the tablets
Click to expand...
For your current CYA of 60, your SLAM level is 24. Thats pretty high, but could be doable.

If you choose to add dichlor, every 1lb of dichlor will add FC of 3.0, but also raise CYA by 2.7. So add 3 pucks and you are at 70 CYA, then you will be 100+ in no time. We see it all the time when people just solely use pucks.
 
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One (hopefully) last question. I just did a calculation and if I drain and replace about 8000 gallons of water (~24,000 gal pool) I could lower my CYA from 60 to 40 at a cost of $40-$50 subsequently lowering the FC SLAM level from 24 to 16. If desired I could then use the 40 or so pounds of dichlor pucks (post-SLAM) that I have sitting around (or a portion thereof) to raise the CYA back to 50 or 60 which would offset the cost of the water.

I don't really care about the cost of the water but it seems like it would make obtaining the proper SLAM level easier as well as using less chlorine. Good or bad idea? I've been reading these forums about recommended CYA levels and it seems there are varying opinions but most are in the range of 40-60. I live in San Jose CA where our mid-summer temps average around 80-85 deg with plenty of sun so I'm thinking 50-60 would be a good place to end up.
 
Snowshoe said:
Good or bad idea?
Click to expand...
The more you drain, the easier the remaining battle is. Are there any ground water concerns by you ? Do you know your water table depth ?

The UV / heat will be a concern on the plaster as well. I would do it anyway, but tent it with a cheap tarp from harbor freight, and either rig up a sprinkler or water it myself every 30 mins. I'd likely be there keeping close tabs on the process anyway. Watering the shell would keep my idle hands busy at least. :ROFLMAO:


The only downside to raising the CYA with tabs is that it would take a while. You may lose too much FC per day to make the wait worthwhile.
 
Snowshoe said:
One (hopefully) last question. I just did a calculation and if I drain and replace about 8000 gallons of water (~24,000 gal pool) I could lower my CYA from 60 to 40 at a cost of $40-$50 subsequently lowering the FC SLAM level from 24 to 16. If desired I could then use the 40 or so pounds of dichlor pucks (post-SLAM) that I have sitting around (or a portion thereof) to raise the CYA back to 50 or 60 which would offset the cost of the water.

I don't really care about the cost of the water but it seems like it would make obtaining the proper SLAM level easier as well as using less chlorine. Good or bad idea? I've been reading these forums about recommended CYA levels and it seems there are varying opinions but most are in the range of 40-60. I live in San Jose CA where our mid-summer temps average around 80-85 deg with plenty of sun so I'm thinking 50-60 would be a good place to end up.
Click to expand...
You can use the dichlor later, it won’t go to waste. Chlorinating liquid is usually cheaper per ppm of FC and works faster.
 
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Newdude said:
The more you drain, the easier the remaining battle is. Are there any ground water concerns by you ? Do you know your water table depth ?

The UV / heat will be a concern on the plaster as well. I would do it anyway, but tent it with a cheap tarp from harbor freight, and either rig up a sprinkler or water it myself every 30 mins. I'd likely be there keeping close tabs on the process anyway. Watering the shell would keep my idle hands busy at least. :ROFLMAO:


The only downside to raising the CYA with tabs is that it would take a while. You may lose too much FC per day to make the wait worthwhile.
Click to expand...
I actually drained the pool about 80-90% 2 years ago (only about 1/2 of the deep end water remained) as the CYA was off the charts from years/decades of using dichlor tabs. I had just rented the house a couple of years before that and was ignorant about CYA. I don't know the exact water table depth but I'm sure draining 1/3 of the water shouldn't be an issue. My coworker has had her pool sitting empty for several months for major repairs with no issues.

As far as raising the CYA with tabs post-SLAM, as PoolStored pointed out above (albeit slightly different numbers), I did a search and Taylor claims:

Both dichlor and trichlor are over 50% CYA by weight. For every pound of trichlor added (roughly two 3" tablets) to 10,000 gallons of water, the CYA increases 7 ppm.

So for my 22K gal pool, 1 pound of dichlor should raise the CYA by approx (10/22)*7 = 3.2 ppm so it shouldn't take that long to raise the CYA from 40 to 60 if that's where I decide I want to end up.
 
I smell what you’re stepping in but it’s not a good idea.
Aside from their cya issues & acidic properties Pucks take too long to dissolve to effectively perform the
SLAM Process. Then there’s the issue of adequately gauging all their effects as they dissolve.
Save the pucks for vacation & use liquid chlorine for the slam. You will always know what your cya is & be able to accurately dose & maintain the proper fc level for that cya which is the most efficient way to eliminate algae.
Lowering the cya would be helpful for the slam but isn’t completely necessary.
 
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Mdragger88 said:
I smell what you’re stepping in but it’s not a good idea.
Aside from their cya issues & acidic properties Pucks take too long to dissolve to effectively perform the
SLAM Process. Then there’s the issue of adequately gauging all their effects as they dissolve.
Save the pucks for vacation & use liquid chlorine for the slam. You will always know what your cya is & be able to accurately dose & maintain the proper fc level for that cya which is the most efficient way to eliminate algae.
Lowering the cya would be helpful for the slam but isn’t completely necessary.
Click to expand...
Thanks but I never planned on using pucks for the SLAM, only using them post-SLAM in order to raise the CYA a bit after lowering it with a partial drain. There was some talk previously that at a CYA of 60 I was in the "harder to slam zone" so since I have 35-40 lbs of pucks sitting around I rationalized that the cost of a partial drain could be offset by using pucks that are no longer being used.
 
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Snowshoe said:
Thanks but I never planned on using pucks for the SLAM, only using them post-SLAM in order to raise the CYA a bit after lowering it with a partial drain. There was some talk previously that at a CYA of 60 I was in the "harder to slam zone" so since I have 35-40 lbs of pucks sitting around I rationalized that the cost of a partial drain could be offset by using pucks that are no longer being used.
Click to expand...
Oh ok, that’s fine 👍🏻 sometimes its hard to get things across in print 😁
The important part is that you know what you’ve got (because of your testing),
you know where you’re going (How Clear is TFP Clear? )
& how to get there
SLAM Process
(because you know what each thing you use will do) 🤩
SLAM ON!
 
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