Pool Calculator; useful?

[JimK]

I heard about this pool calculator here and was under the impression it was good tool to use. I thought it would be very useful for calculating dosages for my pool.

http://www.poolcalculator.com/

However, recently I read a post here where it was said that (I'm paraphrasing) "...we don't particularly like that pool calculator here..." and another that said "...it's good for some things but not for others...."

So I'm confused about whether or not the pool calculator is a good tool to use or not. Can anyone clarify this?

Thanks.

[AnnaK]

I use it. Like any tool, it has its problems. Under some circumstances its accuracy is not the best from what I understand. But then, maintaining balanced pool water doesn't need to be an exact science given that we're working with ranges of levels and goals. For my needs, it has always been good enough. Its strong point is that it's HTML based and can be run offline if you save it to your local device. The alternative is the Bleach Calculator which is an executable file and runs on Windows OS. I'm on a Mac and haven't used that tool.

[waterbear]

Biggest problem is that it gives too much info all at once and also seems to give a lot of precision that just isn't there. If you don't know how much water your pool holds (and I don't mean to the nearest 100 gallons! then it is an estimate at best.
It also does not tell you step by step what to adjust first and some of the info on how pH is changed by added a certain chemical does not take into account pH rise from CO2 outgassing and the effect of different TA levels and whether there are non bicarbonate buffers present also. We have had people try to 'correct' for the pH effects of adding a chemical with (expected by us) disastrous results.
IT can be a useful tool in the hands of ewho understands pool water chemistry but for the average user it ir more likely to get you into trouble.

[Watermom]

One we prefer to suggest for people to use is this one: http://www.poolforum.com/zxq/BleachCalc262.exe

It was created by a forum member (Michael Smith). It is called the bleach calculator but it actually has more calculators than that. Just click in the upper left hand corner and you'll find quite a few more.

[JimK]

.....
IT can be a useful tool in the hands of ewho understands pool water chemistry but for the average user it ir more likely to get you into trouble.

Yikes. So it sounds like I shouldn't use it to calculate dosing for my pool.


One we prefer to suggest for people to use is this one: http://www.poolforum.com/zxq/BleachCalc262.exe

It was created by a forum member (Michael Smith). It is called the bleach calculator but it actually has more calculators than that. Just click in the upper left hand corner and you'll find quite a few more.

Thanks. I'll give that one a try.

Just tried it. Every time I try it I get an error message "run-time error 13 type mismatch". Am I doing something wrong?

[Watermom]

I don't know. I just clicked on the link and downloaded it again and it worked for me. I'm no computer geek, so I can't help with the techy stuff. Maybe someone else can. I'll ask Ben to look at it for you. In addition to knowing about pools, he is also one of the techy computer geek people!

[rannrich]

Watermom - Thank you for the link to the pool calculator, this is the first time I have seen this. I am not fond of the first one that was referenced so I try to do the calculations myself but apparently I am not very good at it :( - hopefully my problems will disappear now.

JimK - I just downloaded the calculator and it is working.

[Watermom]

Good! Glad to be of help!

[Shifty]

Jim,

I don't think waterbear is telling you not to use the pool calculator, rather saying "proceed with caution." If you can reasonably estimate the volume of your pool (there is an estimating tool at the bottom of the calculator) and you know how the different chemicals react with one another (i.e. trichlor raises CYA and chlorine, but is acidic and lowers pH), it is a useful tool to use. I find myself mainly using the pool calculator for doses of bleach and borax.

[AnnaK]

I second what shifty wrote. I can't use the bleachcalc because it's a Windows executable and I run a Mac. The Pool Calc is HTML based and runs on any platform. Like you, I use it for bleach and Borax calculations and occasionally for "effects of adding xyz". It has never lead me wrong but I now have enough experience with my particular pool to know when I should question any results obtained. The caveat I follow is "add half now, test, add more later".

[tnalaskan]

I started using the pool calculator this season. So far, so good. Have found it to be very helpful. Able to keep all levels where they should be. Pool is crystal clear.

[JimK]

Jim,

I don't think waterbear is telling you not to use the pool calculator, rather saying "proceed with caution." If you can reasonably estimate the volume of your pool (there is an estimating tool at the bottom of the calculator) and you know how the different chemicals react with one another (i.e. trichlor raises CYA and chlorine, but is acidic and lowers pH), it is a useful tool to use. I find myself mainly using the pool calculator for doses of bleach and borax.


I second what shifty wrote. I can't use the bleachcalc because it's a Windows executable and I run a Mac. The Pool Calc is HTML based and runs on any platform. Like you, I use it for bleach and Borax calculations and occasionally for "effects of adding xyz". It has never lead me wrong but I now have enough experience with my particular pool to know when I should question any results obtained. The caveat I follow is "add half now, test, add more later".


I started using the pool calculator this season. So far, so good. Have found it to be very helpful. Able to keep all levels where they should be. Pool is crystal clear.

Thanks. I appreciate the clarification and feedback.

[CarlD]

Some use it and swear by it. I never do.
I figure 1 gallon of <n>% bleach in 10,000 gallons of water raises FC by <n>ppm. It's a convenient rule of thumb based on the actual formula: (1,000,000/pool vol) * (bleach concentration) * (amount of bleach) = FC increase.

[JimK]

Some use it and swear by it. I never do.
I figure 1 gallon of <n>% bleach in 10,000 gallons of water raises FC by <n>ppm. It's a convenient rule of thumb based on the actual formula: (1,000,000/pool vol) * (bleach concentration) * (amount of bleach) = FC increase.

For those of us who are more mathmatically challenged, could you give an example (perhaps using my 20k gal pool using 6% bleach)?

Thanks.

[Watermom]

In 10,000 gallons of water, a gallon of 6% bleach would add 6ppm of chlorine. So, since you have twice as much water, in your pool, it would add only half that much which would be 3ppm of chlorine.

[AnnaK]

Figuring bleach is pretty easy, but how do you calculate borax or baking soda? I'm one of the mathematically challenged.

[JimK]

In 10,000 gallons of water, a gallon of 6% bleach would add 6ppm of chlorine. So, since you have twice as much water, in your pool, it would add only half that much which would be 3ppm of chlorine.

Thanks. I wasn't clear about parts of the equation, such as the units for the amount of bleach (ounces? gallons?) and the part about concentration (for 6% bleach, would I multiply by 6? or 6%?), but your example clears it up.:)

[Watermom]

Anna, I never calculate borax and baking soda. I just make a judgement on how much to add and do small increments until the target is reached. There are so many variables that affect pH and TA that it is kinda hard to have an exact formula for them.

[AnnaK]

For pH, I agree, but alkalinity is pretty straight forward.

[392papa]

Watermom.....thanks for the link...that will be a big help getting me started on BBB!!!:)

[dansdad]

how do I get the bleach calc? If its an executable file how do I get it ??/ I have a windows laptop and an iphone