Using a Saltwater test kit

[Kohan Bros.]

I've been using a saltwater test kit for my cycling 75 gallon. I've been getting some funky results for already being 3 weeks into the cycling process. Is their a difference between saltwater and freshwater test kits , such as different chemical formula for ammonia, nitrites, and nitrates. Any input is appreciated, i am quite flustered with my results from my tests.

TIA

 

[Fishyfanatic]

Yes they are VERY much different. You should invest in a freshwater test kit.

 

[Devilishturtles]

Yes. Definitley.

Get yourself a FW kit, and you'll be much happier with your results.

Most kits come as FW or SW, and just have different charts for the colors. Thus, alot of the same reagants can be used (but not all) but the way it effects the reagants are different for FW and SW, meaning you will get different results.

 

[Kohan Bros.]

Thank You Thank you
I was so worried that my tank was screwed up because all it was reading was ammonia.
Thank You

 

[malkore]

some test kits can work properly on FW and SW. Some cannot. pH and hardness tests won't work...but phosphate and nitrate tests are 'platform independent' (can you tell I'm a computer geek?)

AT the end of the day, its best to buy kits for the type of tank you run, so you don't have to guess which kits are interchangable.

 

[TomK2]

This is from another thread titled "test kit - stupid question?" I got an answer from a manufacturer:
"The ammonia kit can be used in fresh water.
The nitrite kit can be used.
The nitrate kit can be used but you will need to divide your results in half when using in fresh water.
The pH kit will not work in fresh water.
The phosphate kit, the low range nitrate kit, the calcium kit, the copper kit and the alkalinity kit will all work as is in fresh water."

I just got an email from technical support at Aquarium Systems (wow - didn't think I would hear from them so fast, nice service!) Apparently only the PH kit can't be used in both FW and SW. I can't remember enough chemistry to figure out why the nitrate kit would read twice as high in FW, but at least I get to use my old kit for a while. Now my next dilemma -


This may not apply to your kit tho. Remenber, chloride lowers the nitrate results, so SW nitrate color charts and kits have been altered to compensate for this, hence a SW kit gives a false high nitrate level when used in FW.