Strange Problem

[DHousteau]

I am not sure which Topic heading this should be posted under as I am not really sure what is happening. I have had my above ground pool (installed half way in the ground) for about 7 years now without issue. I live in Louisiana and keep it covered, treated and filtered during the winter months. I uncovered it about 4 weeks ago to find an absolutely pristine looking pool with a good chemical balance. I brought up what was lacking and treated for algae.

The pool remained pristine for 2.5 weeks. Then suddenly after being away from home for two days I returned to find 100% of every pool surface under the water covered in a very light purple powder, including all of the ladder. This powder dusts off immediately with an easy touch and can be vacuumed away, but it comes back. After about three vacuumings the surfaces remained clean for a while, but now my wife tells me (I am currently out of town) that the purple covering is back.

Has anyone ever encountered anything like this before? Is this a natural event, or do you think someone may be messing with my pool when my back is turned?

Dave

[lbridges]

You should test before acting, but purple precipitate in pool water is usually due to chlorine oxidizing manganese (maybe overzealous yard fertilization?).

More chlorine should make it turn into a powder again until it's all gone and it can be vacuumed away (vac to waste, don't let it just run back into the pool through the filter to be dissolved when chlorine gets low and start the cycle again).

[DHousteau]

Thank you for this reply. What you say is really interesting as I do not add lawn chemicals at all, but do live in the middle of sugar cane fields. It is possible I could have gotten crop dusted, but it is not that time of the season. My chlorine level is very high. I generally keep it that way out of season when my pool is covered. Would more shock do the trick you think? I will add more chlorine and vacuum the waste outside the pool when i get back home in a week. I did not do that last time and went straight to the filter. Possibly that is why it just came back. I will have my wife dump in more chlorine and shock until I make it back home.