Hi Phosphates

[mkamp1515]

My pool is free form, 36ft long and 24 ft at its widest and 16 ft at its thinnest. It holds 20,000 gallons as it is 3.5ftx5ftx4ft on the depth. It has a SWG and Tahoe Blue Pebble Tec. I would really like to get the phosphates down. Will multiple treatments of PhosFree work? I know it is expensive but I do not want to floc if I do not have to.

[mkamp1515]

OK. Phosphates still high (2000-2500) . But my pressure on my filter is up only a little. I thought it would go up much higher...but it jumped from 17psi to 22psi and back down to about 19psi over a 6 hour period. I guess since I just cleaned the filter out, washed off all the DE off the grids, and replaced the DE is why my pressure is not just climbing and climbing. My new numbers are this:

FC and TC 3.0
pH 8.0 (a little high)
TA 70 (a little low)
Cal Hard 160
CYA 40

The guy at Leslie's told me it would take a week or two for the Phosphates to clear. He also indicated I should add Alk increaser and then acid to bring up my TA and lower my pH. Does this seem like good advice? I do use the Jack's Purple Stuff weekly to keep scale from forming. Seems to have worked so far as I have consistent high pH and I am always adding acid (SWG and Pebble Tec-1 yr old). Any thoughts??

[bassadict69]

I forget just how much the Phos free will drop your phosphates but it isn't much at all compared to a high 2500ppb reading. It would take MANY treatments to get it down like that.

[mkamp1515]

Well, finally got the phosphates down to a more acceptable level. Still a little more to go as they are in the 300-500 range. It has taken two 3 liter bottles and a 2 liter bottle of PhosFree to take care of this. So, you are talking over $100 bucks and 10-14 days of running the pump way more than usual (been averaging 12-15 hours a day). So my electric bill will spike a little as well. However, the water is clear as a bell. So, if you ever get a phosphate level of at least 2500, you will need to spend a little money and have some patience.

Mike

[cwstnsko]

My experience was different. My pool is 13,500 gallon IG, and my phosphates tested at 2500+. 4 days after the 1st 2l bottle of phos-free, I was down to 300-500. I added a bottle of salt-water magic, and it's now down to 100-200. Did you leave the pho-free in the filter long enough? My bottle said not to back flush for at least 2 days. My filter ia a cartridge, so the phos free will be in there until the next time I service it, which may be a while. I did not see a pressure rise from the phos-free

On thing worth mentioning was that I held the pH at 7.2-7.4 during the treatment and I shocked to 20 ppm Cl to kill the algae at the same time.

[mkamp1515]

Yeah...I left it in for at least as long as the instructions indicated. I have no phosphate now. I found my culprit...Jack's Magic Purple Stuff. Used to help prevent scale and is a metal sequesterant (sp?). Works great, just has phosphonic acid in it. If used per the bottle instructions, your phosphate level will skyrocket. I stopped using it and poof, no more phosphates after the last treatment.

[waterbear]

Bottom line...phosphates are NOT a problem unless you a have repeated algae blooms that cannot be dealt with. If phosphates are not the limiting factor in algae growth then the level is unimportant!

[aylad]

I would use acid to lower your pH first, then add baking soda to raise your alk without raising the pH back up. If you do it the other way around, you'll raise the alk but then lower it again when you add the acid.

And yes, it's Arm & Hammer baking soda--the exact same ingredient as alkalinity up, at 1/5 the price.

I'd stop worrying about the phosphates--once you properly chlorinate your pool, it doesn't sound like algae is going to be a problem for you.

Janet

[jenpen400]

Pool store said my phosphates were over 1000 last year I'm sure they are higher now just watch the clorine. I haven't had any problems everyone who sees the pool want's to know how I keep it so clear and I point my bleach bottles.

jennifer

[mkamp1515]

You are right. I was lured in to buy chemicals I really do not need. I have stopped using them and just kept my chlorine level according to Ben's chart and so far my pool has not looked better. I use baking soda to raise the Alk and muratic acid to lower the pH and that is about it. I did have to raise my CYA recently right before I went on vacation for a week as I was losing my chlorine quickly (was very hot that week 105 degrees everyday). I did throw in a 1 lb bag of shock the day before I left and when I got back home the chlorine level was still between 5-10 which is in line with my CYA level (70-80).

Thanks for the advice.