Nitrate Test Kit - Red Sea Pro vs Salifert

[Myka]

So I've been cheating on Canreef a bit, and reading on some others forums that all the cool kids use Red Sea test kits these days. News to me. So I decided oh what the heck, I'll give it a go. So I ordered a Nitrate kit and a Calcium kit from my LFS (he actually decided to bring in most of the line).

So, FYI these test kits are pricey. Like almost Hanna checker pricey. However, you can buy the refill kit for the Red Sea Pro nitrate kit which is about the same price as replacing a Salifert kit. So it's just the initial cost.

I get the kit, and it's pretty fancy looking - giant box. I open it up and there are all sorts of cool gadgets in the box. A 10 mL syringe, a couple relatively large vials, 3 reagents, a color wheel, and a contraption to hold the wheel.

Pic from Red Sea website.

Here's a video:
https://youtu.be/hLCsylTF00E

First thing, fill each vial with 16 mL of tank water (there is also a high range version where you use 1 mL tank water and 15 mL RO). My thoughts, "Awesome, that's a lot of test water! Lame, I have a 10 mL syringe to fill 16 mL." Grumble. Though a smaller syringe is usually more accurate for measuring. Ok I can deal with it.

Then I add the three reagents as directed. I notice the second reagent, a powder, doesn't really dissolve. Hmm, odd. Then you wait 9 minutes for the reaction. Holy crap.

While I'm waiting for the 9 minutes to elapse I do the entire Salifert testing, with the 3 minute reaction time. My result is 0.2 ppm.

So the 9 minutes are over and I look through the vial using the color wheel contraption (this reminds me of the old D-D Merck phosphate kits which were awesome, so I'm digging this color wheel comparator) which has various shades of pink. I see light blue. Interesting. So I go onto a forum where Red Sea is a sponsor and search for this problem. I find the answer written up from a Red Sea rep that this light blue tint means "zero", and I also find out that the undissolved bits are normal. Ok, I'm feeling better about this now, but I'm wondering why I'm seeing a result on the Salifert kit, but "zero" on the Red Sea.

So I dose my tank with a stock Sodium nitrate solution. According to mathematics, I dose enough for about 0.5 ppm nitrate to my tank volume.

I re-test with both test kits.

Salifert (still) reads 0.2 ppm. Red Sea reads 0.5 ppm. Well this is now really interesting.

So this is just preliminary testing, and I'll be using both test kits for awhile to try to arrive at a conclusion. So far, it looks like Red Sea is winning, and it's definitely looking promising for those of us who are wanting to test tanks with less than 4 ppm nitrate as the Red Sea Pro kit has 6 colors to compare to that are 4 ppm and under. Salifert only has 4 that are 5 ppm and under.

I'll report back as I become more familiar with the Red Sea Pro kit.