Massive algae issues

[Luke978]

Hi all,

I have severe algae issues. I have relied on my local pool store and I've neglected it over the winter, and as a result, the algae is out of control. I decided to go the Cl2 bleach method of shocking the pool because I'm tired of getting hijacked at the pool place.

I purchaced a taylor 2600 test kit which came in on the 28th, and I've been adding 2gal of 6% bleach every evening at 830pm for a week. The 27th was the first day since I started adding the bleach that I was able to carry a free Cl2 residual all day.

The test kit came in on the 28th. and here are the readings I've taken so far:

4/28 8:00pm (before nightly bleach addition): CYA90ppm, Free.4ppm, Combined CL.8ppm
4/28 10:00pm (2hrs after CL2 addition): free15ppm, combined CL1.0ppm
4/29 6:00pm (before CL2): cya80ppm, free 3ppm, combined CL2 .8ppm, alkalinity 60ppm, PH 7.6
4/29 12:30pm (2hrs after CL2) free 15ppm, Combined CL2 1.5ppm

Pool specs: 12000gal 24' round
Pump/filter: Hayward 50gpm sand filter, 40gpm pump

Am I doing this properly? I'd like to avoid draining my pool if I can.

PS: I fully deserve any ridicule I get for letting my pool get in this condition, so please heap it on.

[kelemvor]

With a CYA of 90ppm you need to taret 20ppm FC for shocking. From 0-20 that would be almost 4 gallons of 6% if you've really got 12k gallons. I say that because after adding 2 gallons you hit 15 which doesn't work out quite right in 12k gallons of water. According to the pool calculator (http://www.poolcalculator.com/), 2 gallons of 6% would add 15ppm to 8200 gallons.. or maybe the bleach you used was a little stronger than the label said. Try dosing 3 gallons and see where you get, remember your target should be 20ppm to shock based on the Best Guess chart (http://www.poolsolutions.com/gd/best-guess-swimming-pool-chlorine-chart.html#a). Do that until you can go from sundown to sunup without losing more than 1ppm.

[Luke978]

Thanks for the reply. The bleach I used was some that I picked up on sale at the local grocery store. It was value time bleach, I think. I just picked up some walmart brand stuff today.

I need to make a couple of corrections to the original post:

The test kit is a Taylor 2006A and my filter is a 25gmp sand filter.

Thanks again!

[Luke978]

Quick update:

I added the bleach as you suggested and finally got to 21.5ppm last night, lost 5ppm by morning and added 9qts of bleach. I took a sample at 1:45 today and got 20.5ppm, so I added 6qts. It looks like I'm starting to get ahead of it. Thanks again!



I have a little more clarity on the pump/filter. The filter is a Hayward s144t sand filter with a filtration rate of 25gpm at 50psi which holds one 50# bag of sand. The pump is a 1hp 40gpm hayward. Sorry for the lack of info. The stickers on the filter canister came off and i had to do alot of digging to get the right info.

After doing a bit of reading on the forum, I think I'm greatly over-pumped and under filtered. I went to the hardware store today and picked up a ball valve and installed it on the pump discharge. Under normal conditions the filter usually runs at 12psi, so I throttled it back to 6psi after I backwashed. Hopefully that will help the filtration, as I currently have only about 8" of visibility. If this doesn't help, I'm gonna try some D.E.

[aylad]

Looks like you've done the homework--congratulations!!

You're doing it all right--just stay the course and let us know how it's going. :)

[Luke978]

Shure will, thanks.

I may have found a replacement filter, a 300# Hayward S244S for $200 localy. Would this be overkill for my pump?

[PoolDoc]

No, it will work well, BUT you'll need to be careful in your plumbing so that you can deliver 40 - 50 gpm to the filter during backwash. If you can do that, you should get excellent performance from that filter.

If you can send pictures of your pool & piping layout (send to poolforum@gmail.com) AND tell us the model of pump you have, we can probably make some suggestions.

[Luke978]

Hi Ben,

The pump is a hayward s48e48a04, 40gpm 1hp. I can't take a pic of my setup at the moment, but I replaced the pump discharge hose with sched. 40 1 1/2" pvc piping. My drain hose is also 1 1/2".

[PoolDoc]

That's the AO Smith motor number; possibly on a Hayward Power Flo or Power Flo LX. You need to look on the plastic part of the pump, where the pipes connect, for a label with an SP number, like SP1540C

[Luke978]

Oops, its a SP1540CFP.

[PoolDoc]

Yeah, it should be OK. I can't find the electrical characteristics on that pump.

You probably need to put a valve between the pump, to throttle flow back some, to keep the motor from overloading. The filter will have so little 'back-pressure' with that pump, that you may create an 'over-flow' situation, which results in overloading the pump.

Do all the piping with 1.5" pipe, and add a 1.5 ball valve between the pump and the filter. You'll need to throttle it a bit during normal operation, but open it wide when backwashing. You should be able to get really, really clear water with that combo.