I meant exactly what I typed. Surfactants are not a problem.
For one the amount of surfactants that is in the ammonia is extremely small. Then they are further diluted by the water. Finally between the carbons and the major water change, there will be little if anything that remains behind. But do not take my word for this, look at the science.
Adsorption kinetics of surfactants on activated carbon
Arnelli1, WP Aditama1, Z Fikriani1 and Y Astuti1
IOP Conference Series: Materials Science and Engineering,
Volume 349,
The 12th Joint Conference on Chemistry 19–20 September 2017, Indonesia Citation Arnelli
et al 2018
IOP Conf. Ser.: Mater. Sci. Eng. 349 012001
Abstract
A study on the adsorption of both cationic and anionic surfactants using activated carbon as well as the investigation of the adsorption isotherms and adsorption kinetics has been conducted. The results showed that the adsorption of sodium lauryl sulfate (SLS) by activated carbon was Langmuir's adsorption isotherm while its adsorption kinetics showed pseudo-second order with an adsorption rate constant of 2.23 x 103 g mg-1 hour-1. Meanwhile, the adsorption of HDTMA-Br by activated carbon showed that the isotherm adsorption tended to follow Freundlich's isotherm and was pseudo-second order with an adsorption rate constant of 89.39 g mg-1 hour-1........
3 Results and Discussion
Surfactant adsorption on activated carbon was conducted by contacting the activated carbon with both SLS and HDTMABr surfactants in the range of time 3, 4, 5, 6 and 7 hours. The data obtained were in the form of correlation between adsorption contact time and adsorbed-surfactant concentration and also adsorption capacity. The data were then used to determine the adsorption types and adsorption kinetics of both surfactants trapped onto activated carbon. Table 1 indicates that the adsorption SLS and HDTMA-Br by activated carbon occurred at the optimum time of 4 hours. The adsorption of both surfactants increased insignificantly after 4 hours. It shows that at the time of 4 hours, the activated carbon optimally absorbed surfactants.
https://iopscience.iop.org/article/10.1088/1757-899X/349/1/012001/pdf
Like I said I never used pure ammonia, only the household with surfactants but no other additives. I cycled about 9-10 tanks this way before I learned to use ammonium chloride. First I got the liquid form from Dr. Tim's but I finally bought a big jug of powdered ammonium chloride and mix the stuff myself.
For those who do not know, Ammonia in water turns into two forms. One is the ammonia gas itself which is NH3. But in water most of the ammonia turns into NH4 which is ammonium. Ammonium chloride is the powdered form of ammonium. One can remove ammonia from the water either by removing NH4 or by removing NH4. As either one is removed the remaining form immediately converts back to the balance of NH3 and NH4 that is dictated by the pH and temp. of the water.
The reverse applies to adding ammonia. In fact, we never actually add ammonia as NH3, we add it as ammonium. Read the label on a bottle of ammonia and you will only see ammonium hydroxide, not ammonia. When this hits the water some part should turn into NH3. However, it is important to understand that by the time the pH of water hits 6.0 virtually any ammonia is all ammonium.
Just to give an idea of this, consider 10 ppm of total ammonia (as shown by ab API test kit) in a pH 6.0 tank at 77F. The amount of NH3 is 0.0058 ppm and Nh4 ammonium is 9.9942 ppm. Raise the pH to 7.0 and there will be 0.0576 ppm of NH3, and that can be harming fish.