Blue flakes precipitating out of water

[Five to one one in five]

I am new to this very comprehensive forum and will be diligently studying all of the material as I have learned my lesson about taking pool ownership / maintenance lightly. I have searched the internet and have not come across anything else like this issue. My water maintenance routine consists of keeping the chlorine level up and adding some acid now and then. So……………….a few days ago I purchased 4 gallons of chlorine at Home Depot and added it to the pool. As soon as the chlorine hit the water it began to cloud. It got extremely cloudy and then after a few hours blue flakes started forming and some falling out of suspension landing on the bottom. I let the filter run (de filter type) for a few hours, vacuumed and then decided to take the filter apart and clean it as it hadn’t been cleaned for awhile and could see that this was going to be a challenge for the filter. When I opened up the filter it was completely coated with a layer of bright medium blue “stuff”. It was as if someone took a spray can of blue paint and coated every inch of the diatomaceous earth in the filter. Before I added the chlorine I used a test strip and the water was very acidic. I had dumped in 2 gallons of acid and some chlorine a few weeks ago without testing. I am guessing that some kind of chemical reaction took place. I added 2 large boxes of baking soda which brought the ph into line and have been running the filter for two days. The water is clear now and has just a little blue sediment on the bottom which should be completely gone after one more vacuuming. The tile grout as does a little of the pebble tec coating has some blue staining.

Has anyone had this happen to them? What was formed? Anyway to remove or neutralize the blue staining?

 

[JamesW]

Sounds like copper.

Is there any copper in the water?

Do you have pictures?

What's the history?

 

[Five to one one in five]

I have no idea about copper in the water. I'll get some pics up but its dark and raining at the moment.

 

[JamesW]

Are you new to this pool?

Can you post a full set of chemistry readings?

What equipment do you have?

Was the blue a turquoise color?

 

[Five to one one in five]

We have had the pool for 16 years. It was drained once when the pebble tec was installed around 7 years ago.

FCI: 10
Alk: 40
ph: 7.2
cya: 20

Equipment.... DE filter, variable speed pump

The flakes and sludge on the de was very very blue, not green at all.

 

[Five to one one in five]

Here is the tile. Well..........it may in fact be somewhat turquoise

- - - Updated - - -

 

[JamesW]

Looks like copper.

Have you used any blue algaecide?

Do you have an ionizer or heater?

 

[Five to one one in five]

Last summer algaecide was used. Used it maybe 3x in total. Heater is broke. I have to leave now but will return later. One more pic to add.

Thank you!

 

[Five to one one in five]

I have thought about it and yes the algaecide that I used was indeed this color of blue. Son of a gun. How can I shock the water and not have this occur in the future?

 

[JamesW]

A drain and refill is the only way to get rid of all of the copper.

However, draining and refilling has risks. The pool could float or the plaster could crack.

Without draining, you can use sequestrant and careful chemistry management to minimize the problems.

Don't use calcium hypochlorite and don't make any big chemical additions.

You can do small water exchanges or even drain and refill at the same rate to maintain a consistent water level and dilute the copper to a lower level.

Also, the old heater is probably corroding and adding copper if it's still in the water path.

 

[Five to one one in five]

Thank you James. Is there a safe algaecide to use occasionally that won't add copper to the water?

 

[jblizzle]

Well there's typically never a reason to use algaecide if you maintain the proper chlorine levels. If for some reason you feel you must use algaecide then use a polyquat 60.

 

[JamesW]

You really don't need algaecide. However, if you want to use some, I suggest Poly 60.