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Test Kits


Staff member
Moderator (Staff)
Nov 20, 2002
Hi all,

We were talking about test kits under another thread, when Rusty suggested it needed to be a separate topic. So, to make this discussion more visible, I've started this new thread about test kits.

This is what I wrote in response to Carol's inquiry about the getting a good test kit:

I have a large kit made by Hagen (Master Test Kit) which has chemicals and test tubes for eight different tests, not all of them absolutely necessary. But it's very well organized and easy to use, and if you loved your chemistry set as a kid, you'll love this kit! The results for all but one test correspond exactly to the ones from my LFS.

I've had trouble with the pH test included in this kit, and ended up buying a Tetra kit for pH, which also gave the same readings that my LFS's tests did.

So, what experiences have you other aquarium owners had?

I've been using Aquarium Systems' SeaTest/FasTest kits. I did some research, and found good recommendations for these. I didn't have any experience with test kits, so I can't speak comparatively, but I'm happy with them. The recommendations list advantages as:

--Good color reference (transparent plastic inserts that are part of the testing vial)
--Granular reagents (fast-dissolving)
--Relatively inexpensive

Personally, I've found them easy to use. The colors have been easy to determine, and they seem to dissolve just fine. I have had one "anomalous" reading--wouldn't know if that's common or rare for kits. It was suggested that there were better kits out there, but that they cost significantly more. It was also suggested that, especially for a person new to aquaria, dry reagents would be better than liquid.

What other opinions are out there? Any comments on the dry/liquid reagent comparison?

The test kits i use are always either Salifert or Tetra, I find them to be one of the best and easiest to work with.
I have it on good authority that many hobbyist kits are a bit hit and miss! My own experience confirms this.
I use electronic probes where possible. These are calibrated weekly, when these are compared to hobbyist pH test kits the differnce can be as much as 0.5, this means my probes are reading 8.13 and the pH kit could read 7.6! Basically the more you spend the better the results. If you can get hold of them Merck kits are lab grade and easy to use but cost about £90 each. That said they last for ages.
Try checking out S.G meters, these also give massively different readings, especially if not kept spotless.

Do you have any experience with the hand-held salinity refractometers? Many people seem to use them here, and they are popular with the LFSs.

I have a hand held refractometer made by Alla, a French company. They are easily calibrated with deionized water. To read SG all you have to do is add 2 drops of aquarium water to the prizm and look through the eye piece. There was 2g per litre difference in salt level when compared with several swing needle hydrometers.
I also have a conductivity probe connected to the aquarium computer. These are OK, but need frequent recalibration to stay accurate. I prefer the refractometer for ease of use and calibration.
I think if the SG is not miles out the actual level is not too important as long as it is stable. If using the swing needle type I would replace it every year as a precaution.

I did that quite recently an found my last one was almost 3 degrees out. But i agree that as long as it's stable and not too low its not so bad.

Jason, have you seen the YSI stuff that TMC sell? I have set up a big reef tank using YSI monitoring equipment, it is pretty amazing all the stuff that it keeps track off. And last time I was at TMC got one of those refractometers for a friend of mine... I agree that its the easiest to use too, it wasnt as expensive as i thought either.