Review on 🌡️ PrecisionPlus: Advanced Back Lit Digital Temperature Aid for Professionals by Bob Fasho

This pH meter is awkward to use because it has to be calibrated frequently. I gave 2 stars instead of 1 because it's not too expensive and it's good enough if you just need an approximate pH. The seller's description says it's a "super accurate and reliable gauge," but it's not. I have a dozen aquariums and I check the pH 3 or more times a week and also check the tap water used when adding fresh water to the tanks. When I received the meter it was off by 0.5 when testing the pH of lab grade test solutions of known pH. The seller also claims that the meter can be used to know when to add more chlorine to the pool, which is not possible. The instrument does not test for chlorine, salt or TDS. It accurately measures temperature and gives an approximate pH of plus or minus 500%. I bought this gauge to replace an old one I had for many years that finally died. This meter is so bad that after 4 weeks I stopped using it and bought another brand. It takes much longer than other gauges to get a stable reading - typically 30 to 60 seconds. This might not be a big deal for testing a pool, but if I test all my tanks several times a week and also check the pH of the new water I use for partial water changes, that adds up to 20 minutes on the test bench, um to work, this is much faster with other counters. My other gauges only take 5-10 seconds to stabilize. The seller boasts that this gauge calibrates automatically, but for actual use this is more of an annoyance than a positive feature. The calibration of all of these gauges will change over time, especially for inexpensive gauges that are not expensive lab-grade gauges. Other meters with an adjustment screw for calibration can be adjusted very quickly and easily if required. I have some calibration solutions, like the link below, that make it easy to dip the meter into a solution of known exact pH, and then I just have to adjust the screw on the back of my other meters to correct for a drift. https://smile.amazon.com/gp/product/B0063MVU5S/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 This gauge has no adjustment screw. Instead, you have to dip the meter in two different solutions, 4.0 and 6.86, while simultaneously pressing and holding the buttons in the correct order. It's supposed to calibrate itself automatically if you follow these steps, but mine repeated the error for one or both test solutions, meaning you'll have to start over. Every time I tried to calibrate it, it took 30 minutes or more. In a few days, its calibration will be off by 0.5 or more when testing solutions with a known pH of 4, 7, or 10. When there are partial water changes in my aquarium, I have to check and correct the new water very carefully. its pH value, because the pH value of my tap water fluctuates between 7.0 and 8.5 from week to week. When adding fresh water to aquariums, I try to regulate the new water so my fish aren't shocked and affected by large pH changes. Aside from the fact that the automatic calibration is cumbersome and time-consuming, you have to use a test solution of 4 and another of 6.56. I have not been able to find ready-made test solutions with the required pH value of 6.86. The meter included a pack of powder to mix with distilled water to make a test solution of 6.86, but it takes even more time to measure and mix, because you need to release the mixture CO2, otherwise the pH of the test solution will be lower than 6, 86 is up - for dissolved CO2 in distilled water. After spending a month with this meter I gave up and bought 2 different instruments with a manual calibration screw. When I'm ready to check my tanks or new fresh water for a water change, I check the first with both gauges. If I get results that are more than 0.1 or 0.2 apart, I test both counters using the standard 4, 7, or 10 test solutions from the link above. A small screw adjustment is much, much easier than messing around with an "auto-calibrate" gauge that is anything but automatic. Skip this gauge and buy one that doesn't auto-calibrate and instead has an adjustment screw on the back to correct the calibration.