Need avice. Water out to lunch.

[meihobo]

This is one sick puppy!
Current state (K-2006 results)

CYA 160+
FC 27 ppm
CC 2.5 ppm
PH 6.9
TA 50
CH 440

No visible algae, water clear
Areas of stains on floor (ascorbic acid spot test indicates metal based stains).

Long history of Trichlor tablet chlorination (CYA accumulation).
Terminated and switched to liquid chlorine.

Request advice on sequence and timing of corrective measures:
70% water replacement
Verify CYA less than 50
FC => 0?
stain treatment (ascorbic acid)?
sequestration (recommended agent?)
PH
TA
CH

Any suggested methods, caveats and other help would be very much appreciated.
Ready and willing to use BBB methodology moving forward.

 

[BoDarville]

Welcome to TFP!

Since you are already faced with having to drain around 70% of the water to get CYA down to acceptable levels, I would go ahead and treat the metal stains before you do the drain & refill. That way, the much of the metal that is in the water will get removed along with a majority of CYA and some of the CH (which is just a little on the high side, BTW).

Here's how to remove the metal stains: Metals in the Water and Metal Stains and more details on the Ascorbic Acid Treatment

Once you refill, run a full series of tests and focus on rebalancing pH and FC. CYA should be where you want it after the drain & refill, but I would test it anyway.

 

[meihobo]

Thank you for your rapid and informative response.

How low must I get the FC down to before AA treatment?
I have 2 lbs AA on order.

Is there a way to speed up FC loss?

Do I need to sequester since I'll be draining?
I have 1 qt. HTH metal control on order.

What do you recommend I maintain the CYA at.

Sorry for so many questions. Any help would be appreciated.

 

[257WbyMag]

Your FC needs to be 0 when starting the AA treatment and your pH needs to be 7.2.

Are you on a well? Why does your water have metals in it? If your fill water has metals in it, then you will always need to sequester it. Cya should be between 30 to 50 in a regular pool.