Algae just refuses to die

May 15, 2018
10
Montgomery
Hey everyone.
Here I am looking for more info.

Read all of the pool school... four times....

Read tons of posts.
Read tons of other sites.
Watched 40+ clean green pool vids.

Followed the pool school.

Intex(Iknow but I'm not rich) 24x54 13,500g pool with upgraded Intex 16inch sand filter with 3kgph pump, total system is 2.4kgph. Put in a through the side skimmer and eliminated the other holes.

Here are my levels per HTH 6 way kit
FC = 14 (been holding that per the SLAM for three days now) it is past the 10 mark and actually an orangish color
PH = 7.2 solid and holding(airiating now)
TA = 110 (lower a bit at a time with acid so to not drop my ph)
Hardness = 240
CYA = 20 (bringing up with pucks because it helps keep FC stable so double bonus)

The pool was sparkling and holding that for a few weeks then we had three + days of rain. Ever since then the pool has been green even with a partial drain from vacuuming the bottom when all the algae feel to the bottom and I cleaned it VIA the exhaust on the filter.

I am at such a loss... I clean the pool to a slightly cloudy keeping the FC at a 5 but within a day I start to see algae growing on the bottom again.

this is driving me up the wall... The pool is rotating the water because the leaves get pulled out VIA the skimmer and the algae grows on the bottom on a swirl pattern.

Backwashing daily even though the meter doesn't show a need, water that comes out is emerald green.

I am finally posting because I am at a loss...

Oh and used Clorox algaecide as well.

Am I just simply missing something? Thanks for any help.
 
You need a more accurate test kit. That HTH 6-way kit is not going to cut it. OTO (the yellow chlorine test) is notoriously inaccurate. I had an OTO tester once and it would show the yellow color of 4-5ppm but, when compared against the DPD chemistry of my good test kit, the FC was barely 1.5ppm. OTO is simply useless as a quantitative measure of chlorine. Also, OTO technically only measures total chlorine (TC=FC + CC) so you really have no idea how much FC is in your water.

You can’t SLAM a pool properly (nor care for your pool long term) without a high quality test kit. It’s really that simple. Algae dies when exposed to proper amounts of chlorine, so the fact that it keeps coming back to your pool is evidence that your testing is off not that your algae is hard to kill.
 
Your biggest problem is that your OTO test kit only measures TC (total chlorine). TC is the sum of FC (free chlorine, good) plus CC (combined chloramines, bad). So although you are guesstimating a reading of 14, you have no idea how much of that is FC vs. CC.

Thus the need for a real test kit with a FAS-DPD test -- it distinguishes between FC and CC.
 
I have a vial that is marked at 5ml, 10ml, 11.5ml, 14.6ml, 20.5 and 25ml
Plus I am looking at K-1003 or K-1004 but not sure 1004 is worth it since the difference between the two are the DPD for FC and I am getting the FAS-DPD which handles that.
 
You need R-0003 on top of what you show you ordered to do CC. That is important to determine the end of a SLAM
 

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Good luck. Seems easier to me to get a quality kit like the TF100 in a single, nicely arranged box.

Take care.
 
Ok so my proper testing kits arrive tomorrow and borate testing strips from some odd company coming in next week.

But yesterday I dumped 10 boxes of 20 mule borax in and adjusted PH with Lowes muratic acid. My pool is an Intex 24x54 but I converted to the through-wall skimmer so it now only holds 13000 gallons.
Anyways today the stuff that has been constantly on the bottom has settled to the bottom again and I put my pump to evac and vacuumed it all out. I have a hose in there now filling it back up.

Tonight I will do a backwash for 3 minutes and a rinse for 2 and keep filling up the pool. We high calcium water here and high TA so I bought extra MA to lower the TA.

I have been battling this algae groth for a month now and held TC at 15+, but without the proper kits I don't know how effective it was. Right now the water looks great and the bottom is visible but I can see the bleaching doing a number.

Again once the kits come in tomorrow and I get home from work I'll be right out there testing and dumping. I want my pool back and I am hoping attacking it with the right stuff keep the algae from coming back.

Will update tomorrow with findings.
 
UPDATE

New kits are in and here we go.

TC = 13
FC = 12 FAS-DPD
TA = 90
PH = ? it was lighter than the bottom number (aeration started and dropped chlorine and another box of 20 mule as I was missing 3 but waiting for the test strips to arrive)
TH = 240
CYA =20? filled the tube but started dot started to hide itself

Not as bad on the bottom so I put the robot in to stir it up, really tired from the vacuuming yesterday and cannot get in the pool today.

So with the box or borat 20 mule aeration and another gallon of 10% chlorine, it is a waiting game to get rid of the rest of it.

I have to say the water has never been this clear with the borax and between it and the major vacuuming yesterday it is way better. Just have to keep the pot stirred to finish it off as it was just a dusting today.

Any advice or just keep on trucking with the chlorine?
 
If your results are accurate, with a higher than 10 FC reading, your pH reading will be off. Check the FC in the morning and if it is below 10, check the pH again. Your CYA is low. I would use PoolMath to find out what you need to add to get from 20 to 30 and get that in the pool. I see you are using pucks and PoolMath will tell you how many it will take to get to your CYA goal. Read up on the SLAM method and just keep the FC up until you can pass an overnight chlorine loss test.

- - - Updated - - -

Also, no reason to retest your CYA anytime soon. Give it a week to retest.
 
No algae refuses to die, it’s playing rope a dope with your chlorine. Once the chlorine drops to a certain point, it’s off the ropes and punching. You need to remove every single leaf, brush, brush, brush and brush again. Be constant with your chlorine, checking your level every 2 hours. Bump back up as needed. In a really green pool, I would go higher than your recommended level. I personally would take it up to 20-25 ppm and maintain until clear.
 
Good luck. Seems easier to me to get a quality kit like the TF100 in a single, nicely arranged box.

Take care.

Red dragon. IMO the nice part of a TF100 kit is all the chemicals are in one place and the directions for testing too. This plus pool math plus the forum and diligence with chemicals and attention to detail is all that is needed to keep your pool sparkling. Maybe next year would be an option to invest in the TF100 kit plus the speed stirrer that helps make the testing quite easy. Good luck with it all! Don’t give up!
 
Yes next year I will have an all in one kit and see how it goes.

Results today

FC=13
TC=~14
PH=7.2 solid
TA=90
CYA=~20 (dot still does not totally go away)


Still waiting for the Borate test strips, next Tuesday and will adjust to 50ppm

Water clarity is now 95% clear with nothing on the bottom. Pump backwashed and Itex robot is in keeping it stirred up until the CC comes down.

I am literally days away now and I can't help but to think that keeping the TC at 15 with the old kit just wasn't doing it the borates have helped because after adding the 10 boxes of 20mule the grren has slowly went away and it has not done that in the last 4 weeks of have a green bottom and sides every day with the high TC. Still to early to tell but I am letting the chlorine drop to normal level so we can get in and run through a trial.
 
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