FAQ: I can’t keep my pool clear and blue. Can you help?


algae green poolQuestion:

I am frustrated beyond belief. The only time the pool is clear is when it’s opened…. I know what I’m doing wrong so it should be really easy to help. I think that when I am adding chemicals to the pool, I’m not adding enough. The instructions on the chemicals…I can’t understand them… I know that my Ph needs to be about 7.2??? and the chlorine needs to be in the middle of the shades of yellow. I use the tester where you fill it with water and add 5 drops of each color. The problem is- I don’t know how MUCH of each to raise or lower one shade level! When I asked you how big the pool is, it had much more water than I thought. We are trying to have friends over and you can never see 3 feet into the murky green water and I am dumping SO much time and money into the water without being able to share it with my friends! I shocked it last night and the color difference was barely seen. I tested and treated again this afternoon and there is no difference other than no chlorine showing up in the test. I will try again but don’t think I ever figured out why the vacuum lost suction last year which really put the hurtin’ on my ‘green to blue’ treatment!



I will certainly try to help! Green water could be algae if there is not enough chlorine/stabilizer in the pool. To treat for algae, add 2-4 gallons of liquid chlorine. Green water can also be an indicator that ph is off. Ideally alkalinity is at 80-100 and pH 7.4-7.6 so if either of those is low add 1# / 10k gallons to raise the level 10ppm, so if alkalinity is low I’d add 2# of alkalinity up. Repeat this process after 2 hours, test the water again, and re-adjust as needed.

You may need to add some stabilizer or conditioner to the pool. That is what helps the chlorine last longer in the water – it should always have a 1-3ppm residual of chlorine which the tablets can do if you put in a chlorinator or floater. Chlorine tablets can come “stabilized” which helps to add the stabilizer to the water, but you can also add additional if the chlorine seems to be leaving really quickly.

Also, run the system 24 hours a day until it clears up – you should see a noticeable difference in the water within 10-12 hours if it is algae, repeat after 24 hours if it’s not quite clear. If you swim and the chlorine level is high just have people rinse off after they get out of the pool. You might also want to pick up some test strips – Aquachek sells a 7 in 1 that you just swirl in the pool and compare to the colors on the bottle – I find it easier than the drop tests to see where the levels of everything fall.