Acid and Base Demand tests: Useful or Not?

[waterbear]

Evan,
You may be one of the few people I know who actually finds the acid and base demand tests useful. But then, as a person who saw LOTS of pools with lots of problems, you might have needed that. But I've never, ever had a need with my two pools. And most people don't. Ben's kits, when he was putting them together, didn't have an acid or base demand test. I STILL use my old PS-233 as my main kit, constantly replacing reagents.
Carl

Well, if you have never had acid and base demand tests to use (OR if you have had them and never bothered to use them since they dor require extra steps) you would not know how useful they can be. An analogy is a magnetic stirrer. Most people do not realize how useful one is until they try one (and Taylor now sells an inexpensive one for home use because they ARE very useful for all the titration tests!) Another example would be those that don't think a good test kit (Like the K-2006) is going to make a difference when they are using strips or a cheap 4 way drop test kit. We've all seen a lot of them and what their reaction is after they finally get a good kit.

Sooooo,,,if you have not used acid and base demand tests do not say that they are not useful since you really don't know if they are or not. FWIW,I know Ben chose not to include them in his test kits and can surmise some of his reasons why. I have a PS-234s myself (and two TF-100s, K-2005, K-1005, K-2006 and a few other non Taylor drop based kits and several specialty kits for such things as chloride (salt), borate, metals, nitrate, ammonia, and orthophosphate) and, while the inclusion of the OTO test (K-1000) in some of Ben's kits (If memory serves me right it was not part of the PS232 but only in the PS-233/PS-234/PS-234s) and the TF-100 is a plus in my opinion, I have found the 2000 series comparator and R-0004 reagent (as found in the K-2005/K-2006) more useful for pH testing than the 1000 series comparator and R-0014 reagent. I also realize that adding two comparators and two different pH reagents would be confusing, add to the cost of the kit, and would most likely lead to newbies (and some experienced users) getting the comparators and reagents mixed up!

[CarlD]

Evan,

Remember: we are primarily working for what works easily and practically for home pool owners.

What problem do acid and base demand tests address than cannot be easily dealt with without them? And are those particular problems common or highly unlikely?

If my pH is high I can use a gradualist approach of adding Muriatic Acid to bring it down.

If my pH is low I can use a similar approach by adding Borax to raise it.

How much easier do those tests make these tasks?

If a pool owner can handle all of his/her issues both when the pool is clear and when there is a problem, without acid and base demand tests, then they are NOT particularly useful for that pool owner. That's simple logic.

Not every tool is necessary for a home-owner.

Carl

[BigDave]

Could the Acid / Base Demand tests be useful to our friends that are reading at either end of the comparator to get a handle on how far off the scale they might be? Should one drop bring the color onto the scale, they're close; Several drops could indicate a more urgent situation. Just a thought.

[PoolDoc]

Guys, I think you're losing track of the OP. Carl, Waterbear . . . if you want to discuss the relative merits of using or ignoring the acid / base demand test, please open a new thread in the China Shop. Personally, I always ignored it, because I have long preferred the little dose, retest and add another little dose approach. But, I never had to work with residential pools that had been mega-over-dosed with acid or soda ash.

Still . . . China Shop, please.

Thanks,

Ben

[waterbear]

China shop is fine with me. Carl, care to split the thread? Post 9 seems to be the place where it went south.
And to answer your question, acid demand test is VERY useful when lowering TA.
Only time I ever had to use a base demand is when someone was not paying attention to their pool chemistry and was using trichlor and had a pH/TA crash and that is rare but I do use the acid demand test all the time.

[CarlD]

Evan,
I'm always open to new ideas. Tell me how to use the acid demand test (I mean, other than directions) and what I can hope to learn from it. Is it REALLY that needed beyond a gradualist approach?

Carl

[PoolDoc]

Evan;

My take on AD & BD tests is that they can provide information someone might LIKE to have, but --- major overdose correction situations aside --- there are few (if any) cases where they provide information someone NEEDS to have.

For example, if you want to lower alkalinity, an AD test will be able to help you estimate how hard that's going to be. But, from a PF 'answer' point of view, what rookie pool users need to be told is STILL "hold your pH to 7.0 or just below until your TA drops to an acceptable level". Functionally, they need to do it however long that takes, and knowing that it might be a long time, doesn't modify the process.

So, as I see it, the AD test adds (to use an awful neologism) "non-actionable" information. You 'know' more, but you can't DO anything with that knowledge.

Granted, it might help with some of the 'Nervous Nellies' or OCD types that show up here. But my experience is, in dealing with OCD's that there is NOT a level of information that actually relieves their itch. No matter how much you tell them, they still want more.

However, if you tell them too much that's not "actionable", this new (and functionally useless) information confuses them or distracts them from paying attention to the USEFUL information, like how low their FC level is.

Anyhow, that's my opinion. But, I'm open to correction.

Ben