Are All Chemicals Created Equal?

[dax]

The reason I ask is that I refilled my tub last week and have all the readings right on using my test strips.  Needed some more chemicals and test strips so I took a water sample along to my dealer.  His computer analysis agreed with my test strip readings except for pH.  The dealer had it at 7.9.  Using the test strip, it was more red than the 7.2 color, but not quite as red as 7.8.  So I called it 7.6.  A 0.3 difference.  No big deal.

However, along with their computer analysis, it also recommends what you need to add to your water.  Their suggestion was 1oz of pH decreaser.  Rather than blindly add the 1oz, I read the bottle.  According to it,given my tub size and a pH of 7.9, I should add more like 1/3 oz.  Seemed like a big difference in dosage between the dealer's system and the chemical instructions. I opted to go with the instructions on the bottle and added the 1/3 oz.  Another test after 30 minutes with the test strips gave me pretty much the same results as earlier in the day, i.e. pH between 7.2 and 7.8, which is what it should be.  Had I added the dealer dosage of 1 oz, I have to believe it would have been closer to 7.2 or lower.  And then I would be adding pH increaser.

So are all chemicals, in this case, ph decreaser, one in the same?  If I had a different brand, would I have to add more or less?  Or is there not that big of a difference between 1/3 oz and 1 oz of this stuff?

[wmccall]

I'd say most are created equal, but it pays to be a label reader.  Look for words like 80% inert ingredients.  And check dosage levels,  I've been MPS that is half as strong, but they recommend you use twice as much, so you have to consider that in costs.

[Mendocino101]

Not really. As Bill says when you read the label you will see some of the differences. I think just about the best or certainly among the best products are made by Vancent I may be spelling that wrong, Sea Klear is one of thier products which we carry along with thier shock and some pool products.

[Steve]

There's a couple of key issues here. First off, there can be differences in the quality of the products themselves. Fillers are more common in dept store brands and price is usually a key indicator.

Secondly, water testing is an imperfect thing. 5 people could read 1 teststrip and see it slightly different. I'm not a fan at all of the test strips and I find the OTO and phenol red drops far more accurate. Lastly, if your dealer does not have the proper volume of your spa in their database, the recommendation on the amount of product required to balance it could vary significantly. A VERY important aspect for all people who get their water tested at their dealer!! Make sure their reading on the volume of water of YOUR spa is accurate!

[dax]

Thanks for the replies!  I'd have thought that one manufacturer's chemicals would be the same as another's.  You learn something new everyday.

I've seen the Taylor Test kits and drops mentioned numerous times on the forum.  And I hear what you're saying about how a diff set of eyes could read the same strip and get dif readings.  However, I really do like the convenience of the strips.  And they have matched up fairly well with my dealer's analysis.  Is a pH diff of 0.3 a big deal?  I didn't think so, but I'm still fairly new to this.

My dealer does have the spa volume correct as it is also listed on the printout they give me after the analysis.  I just thought it was strange that they recommend 1oz while the chemical label recommended 1/3 oz.  Especially given that the chemicals I use are the same as what they included in my start-up kit.

[Steve]

A difference of 0.3 is nothing when you consider the proper range for pH is 7.2-7.8.

Also Dax, keep in mind that the label provides recommendations on a generic volume amount (ie 300 gallons). The dealers water analysis program is usually dead on if the volume is calculated properly so I'm not sure why the discrepancy? Maybe something to ask them...

I know what you're saying with the convenience of the strips but I'm a believer that for that convenience, you are giving up some degree of accuracy as well. Also, be aware of the shelf life of them, as there should be an expiry date on them that many don't realize.

Side note: Make sure you test and adjust Alk prior to pH.

Seems to me like you have a good handle on your watercare!

Steve

[Vinny]

I want to say that in some cases it does and some cases it doesn't.

Buying alkalinity increaser that is baking soda - buy the baking soda. Chlorine can be different and you should look for the most available chlorine - some is 52% and it goes to 62%.

Typically the less of a product you need the more concentrated and potent it is. MPS can be had straight or with  buffers. The one with buffers needs more to do the job and as said more money to use.

Read the label and compare the active ingredient. You'll be able to spot the good stuff from the bad.

AND just because something is a name brand doesn't mean it's better for the job. Case in point - HTH spa chlorine, HTH is a "trusted" name in water care but its spa chlorine is calcium chloride.