PinPoint pH Monitor
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So what color of purple is this? Is it the purple that means a pH of 8.1 or is it the purple that means 8.4? I was getting tired of always guessing which purple it was, unclogging the nozzle of the reagent, and being told every time I had my water tested at the LFS they that my pH was low, when I thought it was high. Finally I brought my test kit (Red Sea) to the LFS and compared it against their kit, as well as their pH probe. You guessed it, mine was off, and even if it wasn’t the color changes were difficult to read. So I had a choice, spend another $20 on a good test kit, a cost which would have to be spent again when the kit was empty, or spend $90 on an accurate electronic one. I opted to buy the PinPoint pH meter by American Marine.
Unpacking the box I found that you get the meter, a probe, and some calibration fluid, enough for one calibration. I hurriedly read the instructions, inserted the 9v battery (not included), and began calibrating my unit. By the way you can also buy a 9v adapter for about 9 bucks but I decided on the battery because I know of at least one person who was getting inaccurate readings using the adapter. I had it calibrated in no time but then realized that one has to adjust the pH figure you are calibrating to by the temperature of the fluid. Hmm, the temperature was 68F so it wasn’t 7.0 I should be shooting for; it was something like 7.15. The same problem with the high pH, 10, was something higher like 10.05. Being that I bought this probe for accuracy I had to recalibrate it, which took a few more minutes. One thing the instructions are silent about is how often you should recalibrate.
Once calibrated it was a simple task to put a piece of self-stick Velcro on the back of the meter and attach the meter to the outside of my tank by the corner overflow. The instructions clearly state that the meter is not waterproof so be sure to place or mount it in a dry spot, not on the hood where it can fall into the tank. I didn’t actually measure it but there appears to be at least 6 feet of wire for the probe, so finding a suitable location should not be too difficult. I placed the probe horizontally in my sump. I did this purposely because the Pinpoint instructions warn you about keeping the probe tip clear of air bubbles, and in my sump, there are plenty of bubbles. I figured that the bubbles would not collect on the tip if mounted this way. Also be sure that the probe is accessible since you should clean the probe tip every two weeks with a toothbrush to maintain proper operation.
The LFS was correct, my pH in the morning before lights on is 8.1, it jumps to about 8.30 after I add the b-ionic, and climbs to 8.45 by day’s end. My next project is to construct a DIY a Nilsen Kalkwasser reactor, which should steady the pH swing.
Was it a worthwhile investment? Most definitely! There comes with it some peace of mind knowing that I can accurately determine my pH at a glance. Very important I think, since pH can tell you a lot about how and what your tank is doing.