AquaChek 561141-02 Salt Water Test Strips for Swimming Pools, 10-Count, 2-Pack

I used every day

The test strips have been accurate when compared with Leslies Pools, and my Chlorinator readings from the pool brain.

My salt system kept indicating low salt. We had some rain and had to drain the pool a bit, then some drought and had to fill with the hose, so it was expected to need to top off the salt. I calculated the amount I needed based on the control box's salt reading and added it, only to find that it barely went up. I got suspicious as I know a failing T-Cell will often read low salt due to the plates failing and not pulling current, which is how the system calculates salt levels (It doesn't really check salt, it just compares the amperage pulled at the current temperature and salt level and calculates it).My salt strips were 4 years old and no longer worked so I ordered a fresh batch and found my pool to be at 3700 PPM, which is at the upper end of normal. That confirmed my T-cell is no longer calculating current. Some say you can clean it in diluted muriatic acid to clean the plates and restore it, but mine is a generic cell and is 4 years old which is about the lifespan of these in Florida where it runs 365 days a year. I fell for it once and didn't double check the salt level and ended up having way too much in the pool when I finally figured out the cell failed, so I had to drain a bunch of water and then refill to dilute it back down to a safe level for the new cell. I wasted several bags of salt and hundreds or maybe thousands of gallons of water, so having test strips to verify the levels is a must. Hope this saves others from my mistakes:-)

Having read the mixed reviews, I decided to give these a shot anyhow. What pushed me over the edge was hearing that a few pool "pros" use them to double-check readings, and have said they are fairly accurate.My tube was marked: LOT A3102 Use By 03/2015**UPDATE: At the end, I have updated my review to include the revised cross-reference chart mine came with**The Good:* Quick/easy to use* Useful accuracy* Great to quickly check cell readingsMixed Feelings:* They have apparently revised their product at least once, if not more, and the cross-reference chart figures are different. This may have led to readout issues for some.Buy it or not?:* Yes, I would reccomend this to someone who wants to do a quick check on their salt level/cell readouts, without having to rush to the pool store. Keep these on hand. Follow the included instructions precisely, and I would suggest using 2-3 strips at once to ensure accuracy.Why I gave 4/5 stars:* Biggest thing is the price, the strips end up being close to $1/ea.The Instructions:The instructions in mine basically stated to put 1" of water in a cup, and put the strip in. Wait until the yellow horizontal string at the top entirely turned black (3-4 minutes, no longer than 12), and to immediately take a reading at that point, using the "peak" of the white etched portion as the reference point.The Details:First thing to note, the instructions which came with the product have a different chart than what they have on their website. My instructions have a cross-reference from 1 to 10, whereas what's on the website shows 1-7. The chart on the back of the tube matches the chart in my instructions. The figures are also different. I wonder if this has caused some issue with accuracy? I used the instructions which came with the tube, and followed them precisely.For accuracy, I tested these against a known-good digital readout. I decided to use 3 strips at once from the tube to determine variance. I put 1" of water in a container, and placed all 3 strips in simultaneously. Between 0-2 minutes, you could see the indicator being etched away, and the yellow strip at the top slowly fading black. At precisely 3:02, the strip went black all the way across, for all 3 strips. I pulled them out, and took a reading.The included chart indicated that my salt ppm was 3790. My digital readout showed 3800. All 3 strips indicated the exact same reference point. Air temperature was 91*F, water temperature was 89*F. That's a decent accuracy for me, and there was no variance between the 3 strips.The Chart: (this one differs from what they have on their website, and matched my digital readouts)1.8 - 3702.0 - 4302.2 - 4802.4 - 5402.6 - 6002.8 - 6703.0 - 7403.2 - 8103.4 - 8903.6 - 9703.8 - 10604.0 - 11504.2 - 12504.4 - 13604.6 - 14704.8 - 15905.0 - 17205.2 - 18605.4 - 20105.6 - 21705.8 - 23506.0 - 25406.2 - 27506.4 - 29706.6 - 32206.8 - 34907.0 - 37907.2 - 41207.4 - 44907.6 - 49107.8 - 53708.0 - 59008.2 - 65108.4 - 7210

Does what it supposed to

Good

Have bought this product several times. Appears to give accurate salt readings. Easy to use and read. A bit costly if you want to measure salt levels often, suggest buying a TDS reader and bench-marking salt levels to TDS. You can use the TDS daily and only use this salt sticks every few weeks when you think the salt levels are dropping or the rebenchmark against the TDS reader.

It seemingly does its job. After leaving the strip in 1” water, trying to determine the ppm line is a problem. There is only fading of colors, so you just pick one I guess.