Originally Posted by Dr Watt
Short of continous monitoring (with digital record) I'll stick to the drops - 800 tests really is just 200 for me (cos I do it 4x). So I made the drop and sample size smaller - because pH test fluid is also not cheap @ $18oz($13usd) a bottle.
Finally, the pH colour code on the Flairform bottle varies and some are too dark, like when you use too many drops, ----- at the correct levels a pH of 6 is light yellow (NO orange) and pH6.1 has a tiny green tint
I started with drop kits before hydro shops appeared in my city. I still have one for emergency use. The indicator solution has changed colour in it's bottle, but it still works as it should. I also make smaller samples than it suggests, and had bad cards. Though you don't need the reference cards after a while. Like you say, you know exactly what colour you want, and feel your as accurate as a 0.1 resolution meter. Anyone who likes tight control of their finances, has to like them.
I wouldn't part with my floating meters though. It's not as good as one you don't even need to pick up and switch on, but that's not a particularly consuming experience. The manufacturers are presented with the same choice of parts for either device, so I can't see any difference in life expectancy is likely. Oddly enough, I have a ph/cf twin screen constant submersion meter, but have never used it as I know my method works. I have had separate cf and ph monitors I doctored to run dosing pumps, but sold them on as my methods changed. The twin thing was about $30 delivered and I could use a camera to record it, or simply a skype account with auto answer to take a look remotely. Old phones are so cheap. It's a bit messy, but might prove that looking at your plants is more use than your tank.
The middle ground of handheld meters, isn't a bad place to be. Not for most of us. Test kits are common in industry though, with scale being unimportant. They always work. Unlike some fancier kit, where breakdowns are to be expected. It's all good.