Hanna Colorimetric Checkers for Alk and Ca? F! yes!!

[lastlight]

Yeah maybe I'm missing something here. The nitrate tests have you looking at a bunch of colours and taking a stab at it.

Ca and Alk have definite colour changes so why would we need those?

[Ron99]

Originally Posted by lastlight

Yeah maybe I'm missing something here. The nitrate tests have you looking at a bunch of colours and taking a stab at it.

Ca and Alk have definite colour changes so why would we need those?

The checkers might potentially give better precision as most quick and easy calcium tests measure to the nearest 50ppm and alk tests to a precision of 0.5. But I guess we won't know until they release more information.

[lastlight]

I use Elos for Calcium and it's good to nearest 10ppm. But yeah Alk is in 0.5 increments.

[Veng68]

What do you think of this?

http://www.sensafe.com/pond_products.php

Cheers,
Vic

[Ron99]

Originally Posted by lastlight

I use Elos for Calcium and it's good to nearest 10ppm. But yeah Alk is in 0.5 increments.

But to get that precision with the Elos you're supposed to do it in two parts which adds time and more margin for error. Let's see how precise the checkers are. Would be nice to have a quick and easy one step test that is precise down to 10ppm or less.

Originally Posted by Veng68

What do you think of this?

http://www.sensafe.com/pond_products.php

Cheers,
Vic

I actually did contact them once but they have never tested in salt water and do not know if their kits would be accurate or not.

[Delphinus]

To me the real "dream" of electronic measurement for Ca and Alk would be to add probes to a controller and the controller can measure the gap between what's added and the consumption rates as a function of time. However the technology really just isn't there for alk testing via probe (I did read an interesting article about this a few months ago about how the physics really just wasn't there for a good electronic Alk measurement) and even though the capacity exists for doing this Ca already, it's really more important to track Alk, or at least, without tracking Alk at same time as Ca, then the Ca number doesn't hold a lot of meaning.

So anyhow now that they claim to have figured it out for Alk, I am naturally curious to see how well it will shape up.

If however it is a colorimeter based tester like then realistically it is just a replacement for manual testing and you can ignore controllers from the equation. In which case it has to be about convenience, accuracy and precision. And repeatability. It's already pretty convenient to test Alk, it has to be one of the easiest tests out there, but for Ca is starts to get a little into the weeds and really into the weeds usually for Mg, so one could maybe accept a little loss in the area of Alk for the sake of gains in the areas of Ca and/or Mg in the hopes that overall to test the big 3 becomes easier than the titration based tests for all 3.

I dunno though. I would like to see the products released and then give them a try. The science alone for the Alk is interesting to me so we'll see how they shake out.

[Ron99]

The tests are not electronic. these are small portable colorimeters probably each tuned to the narrow wavelengths of the particular test they do. So it is just a replacement for our test tube tests. but in the case of things like phosphate, nitrates etc. wher you are trying to match a colour these are most likely more accurate as they don't depend on the colour temperature of the lighting you are doing the test under and a judgement call of what you think the colour is etc.

For stuff like Alk and Ca and Mg that are titration tests with a distinct colour change the advantage might lie in greater precision (which we'll know once they release more information about the checkers) and convenience.

[shrimpchips]

The ease for these tests isn't necessairly in preparing the tests. In fact, they're probably largely the same. But ease lies in the reading - most likely more accurate than judging colour by eye, and because they are most likely not titration-based, will allow for more precise readings. As well, it's repeatability - for the colorimiter, it's going to be fairly consistent day to day. For test kits, the result is only as consistent as your interpretation of the resultant colour.

Yeah to have probes to monitor it real tim would be great. Tied to my dosers, parameters would always be rock solid in a very small range, and you'd just have to recalibrate once in a while as opposed to testing a here and there.