Precision Pool Chemistry: Rudy Stankowitz

Summary

In this episode, Rudy Stankowitz discusses responsible dosing of pool chemicals. He provides tips and best practices for accurate dosing, including standardizing measures, calibrating measuring cups, and using a food scale. Rudy also explains how to create a density-based conversion chart and emphasizes the importance of using consistent suppliers. He suggests using prepackaged doses and digital scales for more precise measurements. Rudy demonstrates the calculations for converting between weight and volume using density and provides examples for different brands of calcium hypochlorite. He also highlights the significance of staying within acceptable ranges for chlorine, total alkalinity, calcium hardness, and other chemicals.

Keywords

responsible dosing, pool chemicals, accurate dosing, standardizing measures, calibrating measuring cups, density-based conversion chart, consistent suppliers, prepackaged doses, digital scales, converting between weight and volume, acceptable ranges

Takeaways

• Standardize your measures and calibrate your measuring cups to ensure accurate dosing of pool chemicals.
• Create a density-based conversion chart to easily determine the volume of chemicals needed for a specific weight.
• Use consistent suppliers and stick to the same brand of chemicals for better control and accuracy in dosing.
• Consider using prepackaged doses and digital scales for more precise measurements.
• Stay within the acceptable ranges for chlorine, total alkalinity, calcium hardness, and other chemicals to maintain a safe and balanced pool.

Titles

• The Importance of Consistent Suppliers
• Creating a Density-Based Conversion Chart

Sound Bites

• "Standardize your measures. Calibrate your measuring cups. Ensure all cups used by the team are consistent and labeled."
• "Create a density-based conversion chart that lists the common pool chemicals, their densities, and the corresponding volume in cups for a standard weight."
• "Use consistent suppliers and stick to the same brand if you want to achieve accuracy in dosing

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Transcript

Rudy (00:00.042)
Hey everybody. Hey everybody. Hey everybody, this is Rudy Stankowitz with the Talking Pools podcast. And I'm here by myself once again. You know, the reason for the season. It's hot as balls out there and Miss Andrea Nannini is doing her best to keep up with all the pools, get them ready for the 4th of July. Make sure everybody has a wonderful swim experience. You know the deal, yada, yada, yada, yada.

Today, the day after the fourth, I hope you all had a kick -ass holiday. Got to spend some good time with family, friends, shoot off some fireworks.

celebrate the nation's birthday in a special way. I was looking through the podcasts for the week and I thought I'd try and keep with the theme and I can see on Monday, this past Monday, the team Down Under, Peter, Shane, and Lee, an episode on responsible dosing. On Tuesday, Dan the man, Dan Lenz out of Chicago, spin touch versus Taylor drop test.

And then yesterday, 4th of July episode, we've got Wayne the man, the ruler of the reagent, discussing essential water tests for pool maintenance. So I decided I was going to jump in on that bandwagon, follow the train, rally up the horses, and dive in a little deeper into responsible dosing. And in calculating what...

Thank you.

Rudy (01:51.498)
So one of the best ways you can control costs is by ensuring accurate dosing of dry chemicals. It's crucial for a pool service company. Given that densities vary and only measuring tool is typically a measuring cup, here are some best practices to help you achieve that goal.

Rudy (02:17.034)
Try standardizing your measures. Calibrate your measuring cups. Ensure all cups used by the team are consistent and labeled. That's right. Get yourself a food scale. Put the cup on it. Zero it out. Add an amount of a specific chemical. And then mark the level at one pound.

or a half a pound if it's an eight ounce measuring cup. Usually we're going to be able to mark a half a pound, but market a true half pound for that product. Train your staff to understand the importance of using the correct cup for the correct chemical to get the correct dose to get the correct measure so they have better control of the pool. You could create a density based conversion chart.

Develop one that lists the common pool chemicals, their densities, and the corresponding volume in cups for a standard weight, a pound, or for my friends down under.

Rudy (03:23.37)
or in grams for my friends down under.

It should be easily accessible to everyone. Make sure you use consistent suppliers. This one I cannot stress enough. Purchase chemicals from the same folks. Use the same brand if this is what you're looking to do. If you want to achieve.

accuracy and dosing stick to the same brand. Otherwise, it'll drive you crazy. I'll talk about that in a minute.

Go with the prepackaged doses whenever possible. I know they cost more, but you know what? If you can find them where it's not that much more of a cost, but you can actually see the benefit in the dose, that's not a bad way to go. Digital scales, like I spoke about, technology, man, use it, it's out there. There's probably a food scale in your kitchen now from some diet that you or somebody in your family went on four years ago that you haven't touched in a day.

in a dog's life. Grab the friggin thing, put the cup on it, zero it out, fill it with the chemical, mark off the half pound mark. There are some apps out there, you know what, be careful with those. I'm just gonna be honest with you. Companies that sell pool chemicals sometimes like to sell pool chemicals.

Rudy (04:51.722)
Make sure that we audit these measures. Make sure we double check these things. Take a look at the SDS sheets. These are going to be key.

Make sure then if we're gonna go through all this trouble that we actually track the usage, track the doses, track what we're adding to each pools and then track what we add to every pool and then go ahead and run a cost analysis. Make sure that you're getting the best bang for your buck.

Team education, educate your customers. I'll give you an example.

just to give you an example. And this is based, we calculate.

Rudy (05:47.402)
So if we want to figure out how many cups of a dry chemical make up a pound, we need to know the density of the chemical. You can get this information right off the SDS sheet. This is something you only have to do once with each chemical, as long as you stick to that specific product, that specific brand.

The first thing you need to do...

convert pounds to grams. One pound is equal to 453 .592 grams. That's just a standard conversion. So you have that number. One pound equals 453 .592 grams. Next, we'll use the density of the chemical to find out how much space or volume that 453 .592 grams will take up.

Density is usually given in grams per cubic centimeter, which means how many grams fit into a cubic centimeter. To find the volume in cubic centimeters, we divide the weight by grams by density. To find the volume in cubic centimeters, we divide the weight in grams by the density. So if the density is 0 .8 grams per cubic centimeter,

we divide 453 .592 grams by 0 .8 grams per cubic centimeter. Finally,

Rudy (07:23.722)
we need to convert the volume in cubic centimeters to cups. We know that one cup is equal to 240 cubic centimeters. So we take the volume we just calculated, divide it by 240 to get the number of cups that we'll need.

So again, easy peasy.

One pound equals 453 .592 grams. Volume cubic centimeters, 453 .592 divided by our .8 grams per cubic centimeter gives me 567.

cubic centimeters. Now I need to convert that volume to cups. So 567 cubic centimeters divided by 240 cubic centimeters, which is what a cup is, gives me 2 .36 cups. So this specific chemical, it would take 2 .36 cups to equal a pound. And it's going to surprise you which chemical this is. So by knowing how to convert between weight

and volume using density, you can accurately measure out the chemicals needed for your pool. Ensuring you're using the right amount, not wasting any product, this helps in maintaining the correct chemical balance in your pool and helps to control your costs. Nobody wants to put in more than they need to. Nobody wants to put in more than is necessary. So looking at these numbers and some products that you're familiar with, let's take a look at two

Rudy (09:01.994)
different brands of calcium hypochlorite. I chose Leslie's Power Powder for one type, and then the other type is Arch Chemicals Refresh, which is most likely what you're purchasing from your local SCP. So doing the math, as we discussed, I can see that the average or... So...

Looking at the SDS sheet for the power powder, the density is listed as 1 .035 grams per cubic centimeter. Again, one pound is 453 .592 grams.

Rudy (09:49.578)
going to take the mass in grams divided by the density in grams per cubic centimeter. There's 240 milliliters in a cup because one cubic centimeter equals one milliliter. Now to calculate the volume in cubic centimeters.

Rudy (10:12.042)
I'm going to divide the 453 .592 grams by the 1 .035 grams per cubic centimeter.

Rudy (10:23.53)
by my density.

Now I'm going to divide my area, which we converted to grams, in a cup, 453 .592 grams again. Now we're going to convert grams. Now we're going to divide the grams by the density of the product. Remember, one pound is 453 .592 grams. So I'm going to divide that by the

density of power powder, which is 1 .035 grams per cubic centimeter, which gives me 438 .12 cubic centimeters. I'm going to take that number now and divide it by the 240 cubic centimeters that a cup holds. And I can see that one pound of power powder is 1 .83 cups. 1 .83 cups. That's for power powder.

a calcium hypochlorite product. Now, let's go on to the refresh and take a look at that so you can get a look at the difference. And this is why it's easiest when you do these measures to stay with the same product, because what I'm about to show you here, what I'm about to explain to you here, is that just because both products are calcium hypochlorite, it doesn't mean that both products have the same density. And in fact, in this one, they do not, because refresh

brand calcium hypochlorite, again, what you're most likely getting from your SCP. The density is 0 .98 grams per cubic centimeter. So what does that mean? Let's go through the math. Let's go through the math again really quick. One pound is equal to 453 .592 grams. Great. I'm going to divide that by the density. So 453 .592 divided by 0 .98.

Rudy (12:20.362)
grams per cubic centimeter that gives me 462 .85 cubic centimeters. Now, since one cup is 240 cubic centimeters, I'm going to take that 462 .85 cubic centimeters that I got and divide that by what a cup will hold. Divide that by the 240 cubic centimeters. And what I get is 1 .93 cups.

Rudy (12:50.218)
That's not correct.

Rudy (12:57.098)
Okay, so now let's compare the power powder to a product you're familiar with. Refresh, probably the calcium hypochlorite brand that you're picking up from your local distributor. Take a look at the SDS sheet. There you will see that it lists the density as 0 .8 grams per cubic centimeter. We start out with our pound, convert it to grams, 453 .592 grams. That will always be the case. That is a

constant it's not going to that is a given it's not going to change the volume again 453 .5921 pound divided by the density which is the 0 .8 grams per cubic centimeter

Rudy (13:43.082)
and here.

Rudy (13:54.538)
I get 567 cubic centimeters. So 453 .592 divided by 0 .8 gives me 567 cubic centimeters. Now I'm going to take that and divide it by what a measuring cup will hold. One US cup, 240 cubic centimeters. So take your 567.

Take the 567 cubic centimeters, divide it by the 240 cubic centimeters that a cup will hold, and you'll see that in order to get one pound of refresh brand calcium hypochlorite, it will take 2 .36 cups. That's a pretty big difference.

Rudy (14:40.458)
So we're looking at 1 .83 cups of power powder to equal a pound. If we switch to refresh brand, now in order to get a pound, I need 2 .36 cups.

That's a huge jump. So power powder, stronger than refresh brand, but refresh brand for the pool professional, much less expensive if you're buying it through distribution. So it doesn't mean that you should jump ship. It just means that you should know as you change from one brand of Cal Hypo to the next, take a look at the density, see what's changed, do the math, or take the easy way that food scale that nobody's using anyway.

Put the measuring cup on it, zero it out, load it up till you get to the one pound mark or the half pound mark, right? Eight ounce cups, so you'd have to load it to the half pound mark. Mark it off, write the name of the chemical on it, and boom, you're good to go. You don't need to do that again. Either exercise until you change brands. But then you should absolutely expect to do it. As in our example, Leslie's Power Powder. After we ran through the math, 1 .83 cups.

We'll give you one pound. However, the Refresh brand calcium hypochlorite, 2 .36 cups to get one pound. It doesn't need to be hard. I just want to make sure that you're putting in the amount you want to put in, that you're putting in the right amount, that you're getting the reaction in the water equal to the dose that you believe that you're putting in. Isn't that important? Anyway.

Rudy (16:29.386)
Those are my tips.

Rudy (16:37.642)
inaccurate dosing.

The other thing that you want to do is pay attention to the acceptable ranges. Pay attention to the maximum range. They're there for a reason.

Rudy (16:57.514)
They really are. Somebody's ran a whole bunch of tests on these things. It's in line with FIFRA, which is the Federal Insecticide Federation of Rodent Act, or something

It's in line with FIFRA, also in line with NSF International, and the APS P, ANSI, which now is the PHTA ANSI. Take a look at your maximum acceptable ranges on products. Chlorine, the back of the bucket, the label says the maximum acceptable level is four parts per million. Guess what? That makes that the law.

I know the CPO class teaches that you can have an acceptable level up to 10 parts per million. I know that your health department code says you can have a level up to 10 parts per million. I'm just warning you that that four part per million thing, it's coming.

Rudy (17:55.242)
I'm not worried about hurting people, but I do want to be in the ideal range, at least in the acceptable range. The same thing with total alkalinity, calcium hardness, total dissolved solids, but I'm looking more so at the levels of other things like copper. Maximum acceptable levels for copper in drinking water is 1 .3 parts per million. Maximum acceptable level in a swimming pool is one part per million. So I want to make sure that I stay in

the ideal range. The same thing with iron, maximum acceptable level point, or the same thing with silver, maximum acceptable level is 0 .1 part per million. So if you start using a silver algaecide, you best make sure that you grab a silver test kit so you can measure that. It's not very hard to exceed 0 .1 parts per million of silver. Same thing, you start using boric acid, the NSF and EPA both state.

50 parts per million should be the maximum allowed in swimming pools. That's a level that's safe for people to swim. So take a look at those things too. Responsible dosing is about more than you getting the desired results. It's about more than you saving money on your bottom end. So responsible dosing is about more than you getting the desired results. It's about more than you.

being profitable. It's also about you staying within levels that have been determined by these organizations to be safe.

Rudy (19:31.146)
Because if anything ever happens and somebody comes and tests the water and you are out of range, well then you're shit out of luck as well. Then you're also out of luck.

That's all I have for you this week. I hope you had a great Fourth of July. I hope you're still having a Fourth of July weekend. I know that's a lot to ask for, that everybody's also off on Friday, but you know what? You guys fucking deserve it. You're out there busting your ass in the heat every day, and I want you to know that we appreciate what you do. We know that what you're doing out there is hard. God bless you. All of you. There's not a one of you that isn't out there busting your ass, and we appreciate you.

Thank you also for making us part of your day, listening to the Talking Pools podcast, checking out what we have to say. We appreciate you guys so much.

Until next time, be good, be safe.