First closing/opening - a little confused about the chemistry


Gold Supporter
Aug 2, 2017
Pool was built last year so first closing/opening was included. In late October, the pool builder closed it for us. To my horror, they dumped in a few products I wouldn't have used myself.
First empty bottle was Pool Magic + Phosfree the next couple were from a "BASOC Winterizing kit" - quart of "Metal Out", 16oz of "Copper Algaecide", and 4 lbs of Dy-Chlor II (56%) shock.
It looks like the copper algaecide was ~23% "copper triethanolamine complex" and the metal out was "1-Hydroxyethylidene-1,1-diphosphonic acid" or CAS 2809-21-4

I called before they opened the pool last week to ask that they not dump any algaecide into my water. They did add 5lbs of shock though.

When I tested the water, I got:
FC 28.0
CC 1.0
TA 70
CH 100
CYA 46
Salt 4000 (pretty sure they dumped a bag of salt in too)
Temp 45* (it was pretty miserable sticking my arm in 1' to get water sample)
PH looked off the charts but i didn't log it because I'm fairly certain I've read here that the tests become unreliable once FC is elevated and

The following day I added water and turned the skimmers back on. When I tested at the end of the day FC had dropped to 19, CC dropped to 0.5 and the water warmed up to the mid to low 50s or so. We have most of the leaves and crud that fell off the cover out now - even the dead mouse. The next day FC was still at 18 and it looks pretty good but I've noticed that the spillover spa seems to be making bubbles that I don't remember last year. It goes away fast, but I don't recall seeing where the water landed in the pool as much as I am noticing now.

Do you think any of these potions are responsible for some of the bubbles I'm seeing? Is there anything I can do about it other than replace some water over time? Reading some of the materials on Pool Magic, looks like they shouldn't have dumped it in when they dumped the 4 lbs of shock in. I also can't help but be irritated that they dumped a metal algaecide in along with a product called "metal out". Too late now I guess. I still have a while before it is swim season, but it will be nice to have the spa back.


Gold Supporter
TFP Guide
Jul 21, 2013
Northern NJ
A few things:

- pH tests are not reliable with FC over 10. So ignore your pH tests until your FC drops
- We round up on CYA tests. If the dot disappears between the 50 and 40 line you call it 50. You can't call it 46 as the scale is logarithmic, not linear. Also CYA test water should be allowed to warm up to room temperature before you mix the reagent in.

At this point relax and let your filter and CL do the work and your FC drop and your water warm up. Thinsg should fall into place.

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