11 Hardness

This is Janine with Pool Zones continuing with series number two and step number two; and that is hardness also known as the calcium reading. Now, we discussed adding the calcium which is like Epsom salt in a previous video. 

So now I am going to discuss the quantity of calcium that you would need to add if you have gone through one of our start-up or construction projects.

Then at the end, you are given specific numbers, so you will be given the alkalinity number that you need to add how many pounds per day. You will also be given the amount of hardness or calcium that you need to add. 

Now the process of adding the calcium is identical to adding any dry acid, mix it up in a bucket, and let’s move along here I’ve showed this video before, so put it in… measure it, put it in a bucket and add water. 

Calcium get’s extremely hot boils so make sure you don’t have the fingers in there, you’re not touching the bottom of the bucket or anything like that, it is extremely hot. 

Of course it’s a chemical reaction when you first add water, and it’s quite disconcerting and if you want to, you know, cook any eggs or anything like that you won’t have enough heat for very long. 

Especially if you put the bucket in the water and you’re adding water to it, you’ll see that it’ll cool down fairly quickly. So, in adding it in this situation, I believe I poured it into the pool, but I do have a preference for pouring it slowly into the skimmer. 

And I said before this skimmer that’s furthest from the pump. What I mean by that is that typically there are two skimmers on our pools we build even the small ones, and it’s the further skimmer from the pump so the chemical has more time to dissolve in the water.


So let’s talk about what the quantity would be let’s say for example you are told to add 20, pounds of calcium. So you would have to add 20 pounds of calcium to bring the water up to the right, hardness. 

So what does that actually mean. How would you add 20 pounds? Would you take 20 pounds, put it in a bucket, based on the principle that I mentioned before, you need to use, very small quantities. Here I am playing with the calcium but that’s before I added water. I certainly don’t do that after I add water. 

So would you add that immediately to the pool, if it’s, again, let’s say 10,000 gallons. No, absolutely not. If you’re instructed to add whatever quantity you are instructed to add, then just cap it at around six or seven pounds, every time you do this. How frequently, well, generally with a calcium, this is very important, you have to wait until the alkalinity, remember, is in the ideal range, so you’re going to be monitoring that. You are given the ranges, they are on the test strips, they are in the book, they are given to you in various pieces of information. 

So, in knowing that your alkalinity has to be balanced before you add calcium, then in adding the calcium, let’s say we had to add 18 pounds, and you will divided it up into three increments of six pounds each time, I would suggest you spread that out over three days. 

Six pounds in the morning, same time, so that it is equal distance, and over three days, let’s say you had a larger you, it might be… I’m going to make up a number; 60 pounds, for some reason your water is ultra soft from a well and it’s a large pool, then what would you do?

In that case, you don’t really want to stretch it out to 10 days that would be far too long. So what you would do is you would do six pounds in the morning and then six pounds in the evening, and repeat that so that would half your timeframe. 

So when adding calcium, it’s the same way. Don’t add more than six to seven pounds each day, and make sure 100% that that alkalinity is in range because if it’s not that calcium is going to precipitate out and it can stick, and it’s a nasty situation, if it does happen, and it does happen. 

So in the next video, I’m going to discuss, Cyanuric conditioner stabiliser. We’ve already covered pH in the previous video, so in the previous video we covered two subjects in one.