Cal-Hypo in an Colored Plaster pool on a DE filter

[efm1972]

My pool is recently installed (plaster completed on May 3, 2012). I have been using Tri-Chlor pucks all season and have seen a recent uptick in CYA due to the heatwave here in the northeast. My CYA average so far this season has been 40 - 50, but last two readings are 90, hence my desire to change to a unstabilized chlorine alternative. My current readings are as follows:

FC - 3.0
CC - 0
pH - 7.6
TA - 100
CH - 250
CYA - 90

I have a few questions regarding the use of Cal-Hypo in a colored plaster pool that is running a DE filter.

(1) Can Cal-Hypo stain an Onyx Ansylbrite (colored) plaster pool irrespective of CH level?
(2) If Cal-Hypo is thoroghly mixed in a 5 gallon bucket of water before adding to pool (and sediment at bottom of bucket is not dumped in), is there any potential for staining or any other problems/issues with using Cal-Hypo in an Onyx Ansylbrite (colored) plaster pool if the CH is 250?
(3) Can using Cal-Hypo long-term cause any damage to a DE filter?

Thanks

 

[Richard320]

You're still going to be adding Calcium, which can eventually lead to scaling on your pool.

Why not just use bleach? No unwanted additives, no premixing.

 

[elwood58]

Your CH is at the low end of the ideal range. Adding CalHypo is going to drive that number up at a fairly fast pace. Using bleach would eliminate this risk.

 

[efm1972]

Thanks for the suggestions on the bleach. I will most likely switch to bleach.

 

[duraleigh]

If your CYA tests 90 again in a second test, I would drain/refill to get it back to 40-50ppm and use bleach for the rest of the season.

Don't use Cal-hypo.....your overdose of CYA will diminish it's effectiveness causing you to likely overdose on Cal-hypo to compensate. Cloudy water and scaling can result.