Age Of The Digital

[Crazy fishes]

A quick post to see what peoples views on measuring water parameters are; who uses colour based testing/ mechanical instruments and who uses digital devices. In recent years, digital instruments have been worming there way into common usage for everything including in aquariums. They are always advertised to be more accurate than 'standard' methods but really are they?? Is it worth the investment to purchase a digital pH meter, thermometer or refractometer.

As always let the discussion begin

Regards

 

[xxBarneyxx]

Think it depends on the quality of the equipment. A decent PH test kit is going to be more accurate then a cheap, badly calibrated digital PH probe.

Testing equipment is only as good as its calibration. You might have a test kit that can measure down to 0.000000001 but if it is calibrated wrong then it is useless. I personally dont use them as you can get very accurate testing equipment for a lot less money and to get decent digital equipment often costs an arm and a leg.

Also in my own opinion it really doesnt matter if everything in fish keeping is exact down to the last decimal point. What is more important (again in my opinion only) is making sure that levels are kept stable. When you start getting "too accurate" people tend to start getting carried away with getting it "spot on" and then end up having parameters that jump all over the place.

That being said I'm a real sucker for gadgets and if I had the money spare and could justify it I would go the whole hog with digital testing equipment. For the reasons above I probably wouldnt do anything different to how I keep my tanks but would give me new toys to play with

I do plan on going for the computer controlled system eventually on the big reef tank but the appeal of this is again mainly the "toy" factor and being able to continuosly monitor and log the water parameters which can show up problems you might not notice with normal testing methods.

 

[dilbert]

I got a cheap ph handheld device. It's often a pain to calibrate it but at least drop tests are even more inaccurate. And you measure the ph often then those drop tests are quite annoying. Even the ph meter is: always "rinse and dry" after use.

Both tanks with fish in got also there cheap ph monitors. So no "rinse and dry". Only switching it on and off as it's battery operated. You can use also a mains adapter but with the battery it's easier to take it off for calibration.

The cleanliness of those calibration liquids is the main problem so I got different bottles and vials.

Those in-built ph meters are important for me to monitor the ph as it gets constantly lowered mainly due to the carbondioxyde in the surrounding air (presumably).

Then I have a salinity meter. It's not very precise (+- SG 0.002) but easy to use apart from "rinse and dry" after use. It comes with a thermometer that adjusts within 10 seconds.

What I use often too is an infrared thermometer. This is useful to determine whatever body temperature around you by measuring the heat radiated from that body. It has an in-built laser LED to point accurately at objects.
I use this mainly when mixing water that is instantly used. You get an instant and precise reading and don't have to wait 10 seconds or so.

 

[SkiFletch]

Remember, any measurement device is only as good as its calibration, accuracy, AND reliability. On the subject of digital thermometers. They are often just thermistors which have been used in industry for decades now. A tried and true technology for sure. The "cheap" ones are usually reliable and accurate, meaning they will display the same value every time they are placed in water of identical temperature. They can however be poorly calibrated. Sometimes being a degree or two off, reading either hotter or colder than the water truly is. Cheap digital thermometers should be verified by either an expensive thermometer, or a decent-quality glass thermometer just to make sure it truly is calibrated properly.

pH probes are another beast. I personally loathe them. As mentioned, their calibration procedures are difficult, tedious, and fraught with operator error at best. And only the most diligent of aquarists will calibrate them properly and frequently enough. And when the probes are not calibrated well enough or often enough, they become woefully inaccurate and unreliable. Furthermore, they burn out over time and need to be replaced yearly. Things aren't cheap either... And when one considers that pH is really not that big a concern in our highly buffered seawater solutions, accurately measuring it becomes less and less important. As a disclaimer, good quality industrial grade pH probes are nowhere near as problematic as the affordable models, but the cost to use one is prohibitive for many aquarists.

I'm sure that'll touch off some debate, but it's just my oppinion

 

[andywg]

I agree with Ski. Calibration is the main thing here. Liquid tests may take a while, but there is none of the calibration.

I may look into some probes in a year or so, but that will be to link my reef up to a computer once I have got a load more SPS in the tank which I feel is a little small to be an ideal SPS farm (only 100 imp gallons). For most mixed reefs you just don't need that sort of control on the readings.

 

[steelhealr]

Ditto with SkiFletch. You really can't go wrong with a digital thermometer. I DO have a pH probe and it IS a pain. Needs to be constantly recalibrated against a known solution and it's a pain. Batteries have to be replaced.

Isn't just fun anyway doing water tests? Reminds me of HS chemistry. LOL. SH