duraleigh said:
Brushpup said:
I'm not wild about the kit test for pH either, but I've gotten used to it. I use and rely on pH meters and controllers on a daily basis to make my living. They are wonderful, but you will not get a good one on the cheap. Reliable ones are very expensive, and even the best need proper storage and frequent calibration to be dependable.
Brushpup makes a very good statement about the pH testing. Cost may be a VERY prohibitive factor but I am going to research digital testers as an option.....but not the standard. I am open to suggestions from those of you knowledgeable about digital testers.
Thank you Dave. I've been meaning to answer back all week, but have been extremely busy every day. As for the small hand held pH units I will give my opinion on a couple. As with anything, we all have differing opinions and experiences. I have nearly 14 years in the industrial water treatment industry and I have dealt with a lot of pH meters and controllers...most of them actually. I don't expect anyone to take what I say as Gospel, these opinons are just based on my experiences. For the typical pool owner, I would think the only practical and affordable choice would be the small "pen" or "stick" types of handheld units.
Of these, there is one I will say emphatically to stay away from and they are the ones made by Oakton. They are usually tan in color. I had several in my early days and they are usually fine for a week or two...sometimes a month or two. Inevitably they need a new electrode (bulb) pretty soon even when used in non extreme ranges...say just for cooling towers. If you are going to extremes using them on steam system waters (higher pH) or something else, forget it, they are often toast before you know it. We recently ordered one of these again for something and thought we would give them another try for the customer. Who by the way, was looking for something more "cost effective". Same result...it didn't hold reliable calibration for a whole week.
There is one however we have seen some moderate success with and they are the ones made by Hanna. The 98121, or the 98127 are ones we have used and been somewhat pleased with. These are around the $100 range. There are cheaper ones made by this outfit and others...around the $40-$50 range, but absolutely stay away from these. I don't care what the manufacturers say, they cannot be trusted in my opinion. Most of the "cheaper" pH electrode replacements cost more than that price, much less the whole unit if that tells you anything. If you ask me, this is just one of the few areas where technology and price simply have not come together just yet. Not sure it will any time soon either.
The mimum criteria you should have with any meter is the ability for it to be calibrated at 2 points...bare minimum. Three is preferrable, but this will usually put you way above the $100 price point. Buffers for pH calibration come in 4.0, 7.0 and 10.0 pHs and are standard in the industry world wide. If you are to keep a pH meter, it is absolutely essential that you have a fresh supply of at least two on hand at all times, 7.0. and the other closest to the range you are normally measuring in. This is arguable, and the reason it really is best to have all three. As a side note...I have many times seen various pH probes that could read a couple of buffers...near dead on, but not be able to read correctly on sample. I can't explain it, but it happens. Perhaps Chemgeek or someone else might expand on this. I should add that buffers are quite expensive, cheaper in bulk, but a pool owner wont need that much. When bought by the quart or less, I doubt you will find them for less than $15-$20 per quart. Not cheap and a quart is likely going to expire before being used. Maybe not, but you get the idea...smaller quantities are even higher most often.
In any event, I would say you can get a fairly inexpensive pH meter that would likely suit the average or advanced pool owner if they are willing to maintain it properly and calibrate it often. pH probes must remain wet and never....ever be allowed to dry out, lest they become compromised. Extended periods of dryness usually spells death for a pH electrode, almost always. Most suggest storing them in pH storage solution which is much like a calibration buffer...often in the 4.0 range. I have found that 4.0, and 7.0 buffers do pretty well. Against most Mfr's suggestion I have kept tap water in mine when used on a daily basis with great success. One thing you should
never do is store them in De-Ionized, distilled, or even high purity R.O. water. It will wash them out and trash them just as badly as dry storage will. I apologize for my verbose reply, but this is my down and dirty on the subject. Having a great meter on hand 24/7 makes it very hard for me to use the drop test, but I forced myself to do it last summer when I got your kit, and I am coming around to it. If I can add anything, or answer any question to help out, I'll be happy to do so.