What is ammonia NH3 & NH4?

The first step is to understand the difference between ammonium NH4 and free ammonia NH3.
There is a lot of confusion about NH4 and NH3 so let us and try and explain.

NH3 (ammonia) is a gas and sometimes called free ammonia it is the toxic part of total ammonia nitrogen (TAN) which is NH3 + NH4.  It is very difficult to work out how much harmful NH3 is present by measuring NH4 and PH and then using a look up table. Most test kits measure NH4 even if they are marked as an NH3/NH4 test kit, this is done by changing the pH of the water sample; you may have noticed how ammonia test kits normally have a small bottle marked harmfull corrosive.

Seneye only measures toxic free ammonia, NH3 and in very low levels.

NH3 is reported in the unit of ppm but this is interchangble with mg/L as it is a gas disolved in water.


How to control ammonia.
All aquariums should have a biological and or chemical filtration to control ammonia. Biological filtration uses bacteria colonies to convert ammonia to less harmful substances. Chemical filters remove the ammonia and lock it away, common materials are zeolite. If you see sudden spikes without a change in stocking or feeding levels than it is likely that either of these methods has failed allowing ammonia to rise to unacceptable levels; a chemical additive or water changes is a good ways to reduce free ammonia levels.

Q. Why does my free ammonia NH3 go up when I do water changes?
A. NH3 and NH4 always form equilibrium with pH and temperature. When we do a water change (especially if you are a lazy fish keeper) the new water will often be harder and higher pH than the water you are removing. This move to a higher pH will unlock NH4 into NH3 and the transition can happen in fractions of a second. The seneye device will report this change in pH, temperature and free ammonia.

Q. Can my seneye be used for cycling my aquarium?
A. Yes the seneye is perfect for setting up an aquarium and making sure the fish are not over stressed by ammonia during the process. However be aware that those embarking on fishless cycling will most likely see a second ammonia peak when real fish are introduced.