Roxy,

Some of us do use pucks, although sparingly. What you are doing is exactly the way I open my pool every year... and it works great for me. Please don't add any extra CYA as of yet, because you already have some dissolving in your pucks, it just isn't measuring. It can take a week before you can get accurate numbers on your CYA.

In the meantime, you do need to add bleach to get your levels up as Dave said. With the CYA in question and low, any bleach you add during the day will burn off before it has a chance to work so it is just a waste of money to add it in the mornings. When you add bleach be careful that you disperse it in away from your tri-chlor feeder.

The tri-chlor pucks are actually acidic and may drive your ph levels down. Once your CYA level is measurable enough to hold some chlorine in your pool you want to at LEAST decrease the number of pucks until you get to your desired CYA.

I prefer to open my pool with the method you are using, since my CYA goes down to nothing every year in the winter. I also am one of the board members that sees a rapid and major increase in ph due to using liquid bleach in their pool (some do, some don't) so for me I start out the year with a low CYA and float a puck or two a week in addition to bleach maintenance. That helps me balance the ph rise from the bleach and slowly raises my CYA levels over the summer. My CYA never gets higher than I can handle this way, and it is simple and economical for me.

Jean