Cal Hypo Tablets

[m100psi]

Linked article: Avoid Over-stabilization

I recently found this article by accident and was surprised not to see it referenced in this forum, since it preaches a similar message. There are a number of posts here about cal hypo tablets, but I didn't see any shared experiences regarding how much they are adding to CH, or issues using them in the skimmer basket. These tablets (Poolife NST) claim they're meant to be used in the skimmer basket, but they also claim to be compatible with "salt generators" and I'm not sure why you would use another chlorine product if you had a salt-based chlorine generator.

If anyone has experience with these, it would be great to hear. I live in an area with soft water, so these seem like they could be a great solution.

Also, any thoughts on why cal hypo tablets aren't more mainstream?

Thanks,
Matt

 

[mknauss]

They certainly can be used. There have been reports they leave behind a goo that is the binder they use to form them.

You can use Effects of Adding Chemicals based on the weight of them to see what they add in calcium for the FC added.

 

[m100psi]

Thanks, I tried it out on the app. I guess it's difficult to compare situations in different geographies. Hopefully, hot, dry summers and soft water mean enough evaporation to counter the CH effect.

 

[mknauss]

Calcium does not leave the water through evaporation. You need to drain the pool to remove calcium.

What is the CH of your fill water?

 

[m100psi]

Oh, yeah, I guess that makes sense. The fill water seemed to be <20 ppm when I tested it. Without specifically adding calcium chloride, it was around 130 ppm, but I think the trichlor tablets I had been using for a while had some calcium chloride in their "other ingredients."

 

[mknauss]

Trichlor tablets would not contain any calcium. The 'other ingredients' could be baking soda or if Blue is in their name, copper.

 

[mknauss]

What type of pool surface do you have? Please add that to your signature. If plaster, you are damaging it with the low CH.

 

[m100psi]

It's a microfusion (pebble-tec-like) surface. I added 25 lb of calcium chloride a couple weeks ago and raised the level to 280 ppm.

Thanks,
Matt

 

[mknauss]

Thanks. Be very careful using cal-hypo. A SWCG is the easiest method of chlorinating.

 

[m100psi]

I'll give it a try, monitor and update in case others are wondering if it's a good alternative to other methods. Thanks for the input.

Matt

 

[mknauss]

For an example, you will need ~8 oz per day during the summer to add ~3 ppm FC to your pool. Each day you will be adding ~1.9 ppm Ca. In a month ~ 60 ppm Ca. During the 5 months of summer, ~ 300 ppm Ca.