For alk, the accuracy of the device keeps me away (+/- 5% of the reading between 4.2 to 14). I keep my alk around 8 so that translates to an inaccuracy of up to +/- 0.4dkh. For a $60 machine, that's unacceptable to me.

Don't have any experience with Ca.

For PO4, I don't love it but I can't hate it either because of all the "guess the shade of green" test, hanna atleast get it "right" to some extend and I don't have to play the shades of green game.

I have all three, i was fed up with color kits, to much judgment involved.

I have the ulr phosphorus, its the easiest of the three and i get the same results each time so i highly recommend it. Ask for alk/Ca i dont like the tips they come with to suck up the reagent, it seems to me you get a different size of air bubble each time this making the results a bit different each time. If you don't use the tips you are using more reagent and the results are different.

The Ca does have one extra step involved in it but compared to the API i used before its nothing like drop, shake, count, drop, shake, count.......

Does anyone have any advice on these tips/syringes?

Also i want to check my PH swing, i have never used a ph meter! How are they? Anyone recommend a good one, Hanna or something else?

That plastic tip that comes with the Alk kit is garbage, period. An insulin syringe is the way to go.

So my question is can you use the syringe without the tip and just pull 1ml or does that throw off the results by using too much reagent?

Discard the tip and the syringe that comes with it and just use an insulin syringe, which you can get at Shopper's Drug Mart. That way, you can measure exactly 1 ml. of reagent. It's very accurate. The other thing you can do is use a 10 ml. syringe with a point on it for your water sample. I can't imagine doing it any other way.

Why do you think that you use more than 1ml reagent if you don't use the tip?

I was wondering the same thing Jess, Huh! did I miss something:question:

My guess is that the reagent is caustic or would potentially degrade the syringe some how and that the plastic tip is made from a different material that can withstand it. I use the tip (that's what she said!) and I'm not very worried about getting too much reagent etc.

I assume that without the tip you dont get an air poocket like you do with the tip thus you are using more reagent and throwing off the results. I have done Alk tests on the same water sample doing both with & without and i got different results. If i remember correctly my Alk with the tip was around 124 & with the tip it was 214.

I could try again just to see and use my crappy API as a comparison to see?

And what about the Hanna nitrate device?

I am using Salifert nitrite test which is pretty coarse. Is the Hanna nitrate tester a reliable substitute?