Red Sea test (Nitrate Specifically) questions

[JNalley]

So, I have both the High Range test provided with the Marine Care Multi-Test kit, and the Low Range via the Nitrate Pro test kit. The Nitrate Pro kit supposedly allows for High Range testing via dilution of the test sample. However, I am getting WILDLY different results between the two tests.

Steps High Range Specific Test:

5ml into vile, add 5 drops A, shake for 10 seconds, add 1 scoop B, shake 60 seconds, add one scoop C, shake 10 seconds, read 10 minutes later. Getting between 10 and 20ppm (which is where I want it really)


Steps Low Range used as High Range:

15ml RODI, 1ml sample, add 5 drops A, shake for 10 seconds, add 1 scoop B, shake 60 seconds, add one scoop C, shake 10 seconds, read 9 minutes later. Getting 4ppm (actually the color is BARELY registering, it's dang near clear with a twinge of pink to it).

Any thoughts on which one I should believe? I bought the Low Range (Pro) test kit because I suspected the Marine Care one was reading too high, but I didn't think it would be THAT far off... Really don't want to spend the money on a Hanna, but would like some feedback on the accuracy of either of these tests... Water testing is the most tedious part of this hobby, and I'm half tempted to cash in part of my 401K to get a reefbot, an IONDirector, or a Mastertronic, lol...

 

[KrisReef]

The problem is that these test kits are probably going to give you the same range of results as the higher end options. Use one regularly and if you get repeatable results with it then figure out how to use it as a guide to keep your parameters stable and don't sweat the real value. Keep your eye on the corals to tell you if they are happy at your stable point. GL!

 

[JNalley]

The problem is that these test kits are probably going to give you the same range of results as the higher end options. Use one regularly and if you get repeatable results with it then figure out how to use it as a guide to keep your parameters stable and don't sweat the real value. Keep your eye on the corals to tell you if they are happy at your stable point. GL!

yeh, that's part of the problem, I was keeping my Nitrates around 15-20ppm for my LPS and Softies (No acros yet, and the only SPS I have are Psammocora and Leptoseris), and I think I accidentally doubled the dose of NOPOX one day which drastically dropped my Nitrates and nearly bottomed them out per the low range test. So I've been working on slowly bringing them back up, but when I reached the beyond point of the low range test, and did the dilution factor, it barely registered as light pink. I was thinking, ok, well I must just be at 2ppm then, tested again today (3 days later) and am getting around 4ppm (like I said pale pale pale pink almost clear water), but that didn't seem right so I went to the high range test and this thing is reading 15ppm... lol... so I'm not sure which I should trust at this point... probably gonna try and pick up a Salifert test or something and see which one it resembles the closest...