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i was wondering about the correct way to use a test strip, the direction tell you to take a quick reading,how much time to you really have, i notice they get darker very quick,not even enough time to write them all down .so whats the correct method,and would anyone know of a electonic tester thats reasonable,that seems to me the more accurate way to go thanks for any info
A liquid reagent kit is the way to go. They are accurate and can test for all of the things you need to know about your water. Ben sells a good one on this site. The one Walmart carries for around $15 is enough to get you by. The strips are not worth the time.
OK,
I'll go down the slippery slope. If you MUST use test strips, then get new ones regularly, at least every season.
WARNING: WHAT FOLLOWS IS BY NO MEANS AN ENDORSEMENT OF TEST STRIPS. THEY ARE NOT A SUBSTITUTE FOR PROPER DROP TESTING.
IF YOU HAVE A PROBLEM WITH YOUR POOL WATER, ONLY POST READINGS DONE WITH DROP TEST KITS OR FROM WATER TAKEN TO A POOL STORE. DO NOT POST TEST-STRIP READINGS!
IF YOU HAVE A PROBLEM WITH YOUR WATER, YOU SHOULD NOT USE STRIPS AT ALL.
Follow the directions on the container EXACTLY--otherwise you will probably get a wildly inaccurate reading. Store them indoors, out of sunlight, or the key on the bottle will get faded.
Cost is not always a clear indicator of quality, but I DO try to get strips that have a CYA test--they are usually higher quality. However, the $30 jar of strips I just tossed don't work as well as the $11 jar.
If you get uneven results across a test pad (not the same shade everywhere) assume the test is invalid.
I get the BEST results when I already have a pretty good idea of the state of my water and all the tests and am looking for a deviation.
if I do NOT know the state of my water, I look only at the FC and the pH pads. And then I only look for deviation--like idiot lights flashing on your dashboard. If the FC pad is white or near-white, I need chlorine. If it's deep purple, deeper than the scale, I'm probably OK. On pH I look for some sort of clear indication of high or low. If I don't see anything drastic, I assume I'm OK till the next test--either later in the day or the next morning. Basically, I'm in a BIG hurry and am looking for a problem I must address RIGHT NOW or if it can wait till the end of the day.
So far, I have found the LaMotte Insta-Test 6 strips to be far superior to all the others I have tried. I've only been playing with them a week or so but they've been fairly reflective of my drop testing--and are $11 for 50, rather than $30 for 100 AquaChek Silver strips.
Again, I do not rely on strips--I try to use drop-testing everyday, but like all of us, between work, home, family, kids I am sometimes forced to take quicker, less-optimal measures. I may not have 2 minutes to test--only 30 seconds to make sure I don't have a problem.
AGAIN: THIS IS NOT AN ENDORSEMENT OF TEST STRIPS. THEY ARE NO SUBSTITUTE FOR DROP TESTING. YOU SHOULD BE USING PROPER DROP TESTING WITH ANYTHING FROM AN OTO KIT, TO THE WALMART 5-WAY KIT, TO EITHER BEN'S KIT OR THE TAYLOR 2006 KIT.
IMHO, electronic testers are not worth the trouble. I have used them in salt water aquariums (and in laboratory settings) but NEVER used them for my pool!!Quote:
Originally Posted by marshallg
Electronic testers fall into two groups. Direct reading meters for such things as pH, ORP, TDS, and Salinity and they require calibration for accurate results. The calibaration has to be perfomed constantly and is more involved than using a drop based kit! There are also other drawbacks (not including price) such as electrodes being fragile and subject to breakage or needing to be stored wet. IMHO, you will spend MORE time with 'wet end' work with one of these than with a drop based kit.
The second group are colorimeters and turbidity meters. Once again, calibration against standards is crucial if you want to depend on the results.
These read the color or cloudiness electronically instead of us using our eyes to compare the results with a color block. You still have to do the test with reagents!
For tests that change color such as chlorine levels or pH they can, in theory, provide much more accurate results but the question becomes whether that amount of accuracy is necessary for our purposes. Given the price involved the drop based kits are the clear winners again! If you do decide to go the route of a colorimeter you want one that uses liquid (or dry) reagent tests and not one that reads test strips!
There is a difference between precision and accuracy. Electronic meters can give you a more precise reading but it does not mean that it is a more accurate reading. Ben (PoolDoc) can explain this much better than I can without getting overly technical but the bottom line is that a drop based kit is going to be more accurate than a test strip. An electronic meter will give you a more precise reading on the test but if the accuracy of that particular test is +/_ 10 ppm what good does it do you to have a meter tell you your reading is 157 ppm vs 160 ppm? Your actual reading might be 147 ppm or 167 ppm!
Hope this info is helpful to you!
As soon as you buy a drop based kit, you'll realize how lousy test strips are. I had some test strips (2 different brands) and thought they might be useful for quick readings or to confirm my drops based results.
I found that they're not even good enough for that so I threw them away.
Yeah, I had a friend that swore his CYA was below 60 because of test strips. Turns out it was above 150. Now they were cheap Wal Mart strips but still, that's a BIG difference.
Uh-h, WalMart's test strips are mostly made by one of the major strip manufacturers. They may be cheaper, but they aren't likely to be any worse!Quote:
Originally Posted by DavidD
PoolDoc.
I use test strips for the exact reason above....when I want to quickly make sure there is at least some chlorine in the pool...usually as I'm running out the door. If the strip has any purple, I know I'm ok for the time being...and will make sure to run a "drop" test as soon as I can. Works great for me...I've yet to have an algae bloom (knock on wood). :)Quote:
Originally Posted by CarlD