Help: how to clean cloudy water with ash/dirt

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
34,798
Laughlin, NV
I have a 1/2 hp Superior sump pump I got via Amazon. It pumps about 7 gpm through a 50' 3/4" hose.
To get the higher rates, you need to use a 1.5" or 2" hose that is not very long.

With an Exchange, your rate is typically dependent on how fast your fill water can put water in the pool.
 

leohan

Member
Dec 24, 2020
12
CA
Here is the latest update.

(1) I finally purchased the pump and exchanged the water slowly because my pool is fiberglass. My method is to drain 1 feet of water first, add fresh water back, and repeat this process. I am not sure whether I am too conservative. Can I use a more aggressive approach?

(2) Today, I tested my CYA level again using both test strips and the TFP kit. The strip shows the CYA level is ok (0-40), while the kit shows the level is somewhere 80-90. I know the strip is not accurate, but I would check with the experts here if this disparity sounds normal.

(3) I observed visible algae in my pool. So I poured 3 gallons of pool chlorines during the weekend. As the CYA level is still high according to the kit, which one should I fix first? Kill algae using SLAM method or continue exchange water?

Thank you!
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
34,798
Laughlin, NV
Your method of draining wastes a lot of water. Essentially you are removing ~10 to 15% of your water, then mixing in fresh water, repeat. So your CYA drop is very small for the amount of water used.
Your TFP test kit (not in your signature) is correct. The strips are guesses.
Follow the SLAM Process once you get your CYA to 40 ppm or so (a 50% exchange, all at once).

Read the Exchange portion of Draining - Further Reading
 

leohan

Member
Dec 24, 2020
12
CA
Thanks again. I did not know this method before. Following the instruction, I finally got the CYA to 40. It is very efficient (not wasting much water).

Now I started the SLAM process. The instruction here says "Brush and vacuum the entire pool once a day". I only have a Polaris 280 cleaner. My previous pool guy always told me to use the robot and filter to clean the dead algae. Just want to confirm whether this is the right way.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
34,798
Laughlin, NV
You need to manually brush. That breaks up any biofilm on algae to let the chlorine get to it. The Polaris can be used to vacuum up the dead algae. The Polaris is not very good at capturing fines and thus you may eventually need to do some manual vacuuming.
 

leohan

Member
Dec 24, 2020
12
CA
I finished the SLAM process and passed the over night chlorine test. The water becomes beautifully blue, though think the pool water is not 100% clear yet.

Thanks, @mknauss for your help.

There are still some very fine debris at the bottom of the pool. I guess this is the reason the water is not super clear yet. When the cleaner runs, it causes the water cloudy.

Based on the discussion in other threads, I guess there are two possible reasons (not sure which one is the cause):
1. low level of algae bloom.
2. the ashes/debris blown to my pool from the wildfire several months ago. Though I changed most of the water, the ashes are still in the bottom of the pool.

I know my Polaris 280 cleaner is not good at vacuum fine debris. Should I first try to run the filter continuously for a long period (e.g. 48 hours)?
Do you have any other recommendations?
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
34,798
Laughlin, NV
A cartridge filter typically will filter out any visible particulates. So brushing often and getting the debris to the cartridge filter is the best you can do. Remember, the first criteria for a successful SLAM is crystal clear water.