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Melba
05-23-2006, 09:04 AM
Hello all

If this topic has been discussed anywhere else in the forums, please direct me to the thread. We opened our pool last weekend, a 21ft AG round. Mustard algae patches have already returned. My current readings are as follows...

TC >15
FC> 15
CYA 99 too high, I know
pH 7.4
ALK 127

We are hitting it with shock, NOT using any sticks or pucks with stabilizer in an attempt to bring that 99 down. The pool water itself is clear. We run the pump 24/7, brush daily...etc. Last summer I battled the beast with not very good results. I am convinced I am growing a resisitant strain.

When I had my water tested yesterday, an additional test was run for phosphates. It took a little while but I was told that I had a high phosphate level of about 800 ppb. It was explained to me that phosphates act as an algae fertilizer and this might be why I have a resistant and recurrent algae problem. Of course it was recommended I use a phosphate remover but being an avid pool forum reader, I am reluctant to put additional chemicals in my pool.

So I ask your opinions about this. As always, I value what I learn here in the forum.

Thanks for your help!
Melba

KurtV
05-23-2006, 09:25 AM
...

We are hitting it with shock, NOT using any sticks or pucks with stabilizer in an attempt to bring that 99 down. The pool water itself is clear. We run the pump 24/7, brush daily...etc. Last summer I battled the beast with not very good results. I am convinced I am growing a resisitant strain.
I think your high CYA is keeping the chlorine from dealing with the algae. With your CYA level, Ben's Best Guess Table (http://www.poolforum.com/pf2/showthread.php?t=365 (http://www.poolforum.com/pf2/showthread.php?t=365)) calls for a shock level of 25 ppm. Stopping the use of the stabilized chlorine (sticks and pucks) is a good start but you're going to have to resign yourself to running a high chlorine level or to a partial drain and refill to lower CYA if you really want rid yourself of the algae.

When I had my water tested yesterday, an additional test was run for phosphates. It took a little while but I was told that I had a high phosphate level of about 800 ppb. It was explained to me that phosphates act as an algae fertilizer and this might be why I have a resistant and recurrent algae problem. Of course it was recommended I use a phosphate remover but being an avid pool forum reader, I am reluctant to put additional chemicals in my pool.
I think you're wise to hold off on the phosphate remover. Chlorine, at the proper level and for long enough, will probably answer quite well. If that fails, several people on the forum have reported success with using polyquat to knock out stubborn algae infestations. I know that Ben touts poly as a better preventative than remedy, but it's hard to argue with success.


Best of luck.

CarlD
05-23-2006, 10:18 AM
Hello all

If this topic has been discussed anywhere else in the forums, please direct me to the thread. We opened our pool last weekend, a 21ft AG round. Mustard algae patches have already returned. My current readings are as follows...

TC >15
FC> 15
CYA 99 too high, I know
pH 7.4
ALK 127

We are hitting it with shock, NOT using any sticks or pucks with stabilizer in an attempt to bring that 99 down.

1) As pointed out, you need to run your FC level up to 25 if you want to properly shock your pool. I don't know what you are using that is called "shock"--it could be all sorts of things. Many of the powder packets of "shock" are di-chlor--and they will also add CYA to your pool, making your problem worse. However, cal-hypo and lithium-based chlorinators won't add CYA--but they will add calcium or lithium. Depending on your calcium level, this may not be a problem--I have no idea what lithium does to water. "Shock" could also be liquid shock--usually sodium hypochlorite--same as bleach and sometimes even the same concentration as Ultra Bleach (6%). Liquid chlorine/liquid shock/bleach is normally the best to use with the least side effects.

2) Your attempt to bring the CYA of 99 down will fail. Sorry to be blunt. There are only two ways to lower CYA. The easiest is dilution--drain 50% of your water off and refill and your CYA should drop to 50ppm. You don't want to know the other way.....:eek: If you don't want to drain and refill plan on keeping your FC between 8 and 15ppm for normal use. This won't hurt you, but you may see your bathing suits fade a little--that's the worst side effect. If you have Ben's test kit or another FAS-DPD powder chlorine test kit, it's pretty easy to measure chlorine levels.



The pool water itself is clear. We run the pump 24/7, brush daily...etc. Last summer I battled the beast with not very good results. I am convinced I am growing a resisitant strain.

When I had my water tested yesterday, an additional test was run for phosphates. It took a little while but I was told that I had a high phosphate level of about 800 ppb. It was explained to me that phosphates act as an algae fertilizer and this might be why I have a resistant and recurrent algae problem. Of course it was recommended I use a phosphate remover but being an avid pool forum reader, I am reluctant to put additional chemicals in my pool.

So I ask your opinions about this. As always, I value what I learn here in the forum.

Thanks for your help!
Melba

Melba, try the other things suggested first. If you follow them with patience and persistance, they work 99.9% of the time. Only then, when you fall into the that 1 in a 1000 group should you move on to trying things like phosphate removers. They are generally pushed as a hi-tech, quick-fix, but that's just hype. There are no quick-fixes that don't boomerang in some way. I don't yet see any evidence of a chlorine-resistant strain of algae--your TC and FC are too low in relation to your CYA to kill an algae bloom. If after two weeks in an environment of CONSTANT FC=25 (at CYA=99) the algae is still there, maybe then you may need a "Plan B". But you aren't there yet.

The best way to get rid of algae is to extend what you are already doing, as has been suggested. Get FC up to 25, and keep it there, checking 2x to 3x/day and adding bleach as needed, run your filter 24/7. Brush your pool everyday, and vacuum to waste everyday. And be patient and persistent. Remember, if your FC drops too low, you are basically back to square one as the algae will start growing again.

Good luck!

waterbear
05-23-2006, 06:57 PM
One final thought for you. Phosphate removers can be a PAIN to use and deal with the aftermath! I would suggest trying them as a last resort when all else has failed as CarlD suggested!

Melba
05-23-2006, 09:14 PM
Thanks to you all for the advice!

We are currently using the cal hypo to shock the pool. How do I switch to regular bleach? How much do I use to kill this algae and then how much to maintain once the problem clears?

Is it true that there is a direct corrolation between high phosphate levels and algae....if my levels are as high as they were supposidly tested wouldn't that make my pool ripe for another bloom later?

What will a phosphate remover do to the pool?


Thanks in advance!
Mel

mkamp1515
05-23-2006, 10:28 PM
Melba, I recently had a phosphate level almost off the charts (2500). I had no algae breakout so I was lucky. I used a product called "PhosFree" by Natural Chemistry. With my phosphate level so high, I had to use 3 large bottles (3liter each) to remove the phosphates. All you do is put it in your skimmer and run the pump. The pressure on your filter my go up. Mine did but then it went back down. After a few days, I backwashed and repeated the process. Took me about 2 weeks. If your phosphate level is 800, you may only need 1 bottle. Depends on the size of the pool. It will not harm your pool. It will make it look "milky" for a while but that clears up in a day or so (Phosfree looks like milk). Anyway, it worked for me.

Hope this helps.

Mike

CarlD
05-23-2006, 10:48 PM
I must disagree. Phosphates only feed algae if it's alive. Kill it, keep it dead, and keep your chlorine levels up so it stays dead and there won't be anything to eat the phosphates.

Phosphate removers should not be used until other methods are no longer able to work. I see no reason to expect our simple bleach method not to work--just because some pool store clerk wants to sell Melba phosphate remover.

Use MWSmith2's free, downloadable Bleach calculator to compute how much bleach you need.

Or remember that 1 gallon of regular bleach (5.25%) adds 5.25ppm to 10,000 gallons of water. 1 gallon of ultra bleach (6%) adds 6ppm to 10,000 gallons. Adjust your bleach based on that, how many gallons you have, and how high you are pushing your FC level.

waterbear
05-24-2006, 07:16 PM
Melba,
I appologize in advance for answering the questions you asked in your last post. My answers can be long winded;):eek::D
My pool water currently has a phosphate level of over 1000 ppm. Phosphate remover manufacturers recommend that anything over 170-200ppm is too high. I have NEVER had an algae outbreak AND I no longer use phosphate removers! One time (when the pool was first put into service) was enough for me to go through the milky pool and the constant filter cleaning for a week. There are several factors that can cause an algae bloom. The most commen is letting your FC levels drop too low or running too low a level of FC for the level of CYA in your pool. Other factors that can affect algae growth are the amount of dissolved oxygen in the water (Borax is supposed to be helpful for that but the jury is still out....but borax is the BEST thing to use to raise your pH when needed) and the amount of nutrients (phosphates AND nitrates) in the water. If you lower the phosphates and it was NOT the 'limiting factor' in algae growth in your pool (because, for example, you also had a high level of nitrates which are also algae foood) then it will be of no help. Every pool is different and had a different 'limiting factor'. If your chlorine levels are not high enough or go up and down like a roller coaster you can have 0 phosphates and STILL have an algae bloom! That is why the advice you are being given is to maintain your FC levels and don't worry about phosphate levels unless everything else fails to get rid of the algae. To find out where to run your FC for the level of CYA in your pool and also how high to bring the FC level when you shock (whether with bleach or cal hypo) can be found here:
http://www.poolforum.com/pf2/showthread.php?t=365

The way you switch to bleach is by just using it instead of cal hypo. To figure out how much you need you might want to download and use mwsmith2's BleachCalc program. Most of us on the board use it...It's great AND free!
Get BleachCalc 2.6.2 here: http://www.hal-pc.org/~mwsmith2/BleachCalc262.exe (http://www.hal-pc.org/%7Emwsmith2/BleachCalc262.exe)

There are cases where high phosphates are the 'limiting factor' and a phosphate remover can be of value but, IMHO, that is only when all other methods have failed. If you don't have algae don't worry about phosphates....just get your CYA and Chlorine levels in line from the first link I posted above.

gregugadawg
05-28-2006, 01:51 AM
I would agree with the fact that typically simply keeping the pool in balanced and chlorine in there 24/7 with a good filtration system will keep algae away. However, eliminating phosphates from the water isn't a pool store gimic, it does give you some leeway as far as algae is concerned, if you were to slip up and allow the chlorine to drop it will take a lot longer for the algae to bloom. I was at first a skeptic of selling this product however I have plenty of repeat customers with nothing bad to say about it. High phosphate level will also cause a higher chlorine demand in the pool. Furthermore either in the 70's or 80's there was proven a direct link between phosphates and algae growth and laundary detergent manufactureres were required to remove phosphates from their solutions due to algae blooms in the water sources.

waterbear
05-28-2006, 02:11 AM
Phosphate removers work if phosphate is the limiting factor in algae growth. they might be, they might not be. Phosphate removers have been used in salt water aquairums for years to help control algae but are only recently being pushed for pools. In aquariums they are useful if the nitrate levels are low, otherwise the algae just consume the nitrates. The same happens in pools. Oxygen level in the water is also a limiting factor in algae growth. This is how borates (Supreme, Optimizer) are supposed to work but once again, if there are high nutrient levels present then they don't work that well. Phosphates were not only banned from detergents becuase of algae problems in bodies of water but because they also had a detrimental effect on reef building marine organisms such as corals and interfered with their production of their calcium carbonate structures that the reefs were composed of. I was actually involved in some of this research in the early 70's at the University of Miami School of Marine and Atmospheric Science in Miami.

I am not saying that they don't work but they should not be the first line of attack. Also, just because there are high phosphate levels doesn't mean that an algae bloom is going to occur. IF there has been an ongoing or recurrant algae problem that is not reponding to more conventional method AND there is a measured high phosphate level THEN, IMHO, would be the time to try a phosphate remover. In these cases they seem to have a high success rate.

I am sure you have plenty of repeat customers that have nothing bad to say about it. So do I. I also have plenty of customers that swear by copper based algecide becuase they just have to pour them in and not worry about checking their chlorine levels or REALLY taking care of their pool until the first time they notice stains in their pool or their hair! IMHO, the simplest solutions to a problem are the ones to try first. If that doesn't work it is then time to try a different approach and be willing to deal with the side effects. For lanthenum chloride and lanthenum carbonate phospate removers these side effects includes a milky pool, rising filter pressure and freqent cleaning or backwashing, and possibly having to vacumn a LOT of precipitated sediment to waste for the week or two that treatment takes.

Finally, to use a phosphate remover when there is not an algae problem even with high phosphate levels in the water is, IMHO, just wasting money on a product that ultimately has no effect on your pool. Same idea as putting in copper to prevent an algae breakout when the water is clean. You are using a product that is not needed to correct a problem that is not present in your pool. If it ain't broke, don't fix it!