[Wet Thumb Forum]-Water Test Kits for Fresh Water Tanks

[Reluctant (MLG)]

Thank you all for your help with my previous question. I thought I would continue it with a different heading.

Following suggestions, I bought a water testing kit. It is for fresh water. It tests for PH, "High PH," Ammonia, Nitrates & Nitrites.

After I got it home and opened it, the ammonia test says it is for fresh water tanks with added salt. Did I buy the wrong thing?

[Matt S.]

High PH test kit generally covers PH range ~7.4 to ~9 or sometimes higher. It provides better resolution of PH differences in these higher ranges. High PH is more commoly found in waters with lots of disolved salts / high alkilinity. It still might be no problem to use this depending on your water. For instance lots of places where the tapwater has high carbonate hardness KH will also have high PH.

Regarding the Ammonia test kits - some can be used for salt water / fresh water, *however*, usually they use less water for the same amount of reagent if it's salt water or give different color scales.. This does suggests there is some difference in the way the reagent behaves depending on water salt content. You need to add more of the reagent to get the same color change - this suggests you could overestimate Ammonia using a salt water test for fresh water. I've also gather some Nitrate test kits give different color charts for salt/freshwater.

I don't know where "Fresh Water with Added Salt" begins and where it becomes "Marine", but if you want to err on the side of caution you might want to get a different test kit.

On the other hand since it seems likely that the ammonia test kit would read high if used for testing fresh water you might get away with it. You might be lead to panic over the soaring ammonia content but that's better I suppose than underestimating ammonia.

Generally you only need to test ammonia when you are first setting up an aquarium or when there's been filter bacteria die of / or fish look sick and you want to rule this out. If you stock lightly and plant heavily from the start you might even get away without testing ammonia at all. You do take a risk as the definition of "lightly" and "heavily" are undefined here.

Two other useful test to consider getting Gh/Kh to understand water parameters.

[dwalstad]

I really like my Red Sea Ammonia test kit. It's a liquid that works well in both saltwater and freshwater. It's easy to use and still working fine after a year.

I conserve Red Sea's liquid reagents by testing 1 ml instead of 3 ml and using about 1/3 of the reagents. I use a white egg carton to do my testing instead of the little glass tubes. I pipette 1 ml into the little cup where the egg was.

In my opinion, the nitrite test kit is very important. Nitrites have caused more problems in my tanks than ammonia-- and you can't smell it.