The only effective eradication of cryptosporidium serpentis is ammonia. I’m not sure of any written solution concentration. I have used a 70/ 30 parts dilution as a preventative. You may want to consider putting the whole unit into a extra large 40 gallon trash bag and spraying proventamite as well. Tying off the garbage bag for 24 hrs. Once you pull the unit out of the bag let it sit and air out for another 24 hrs. Wear a mask as well. By the way, that’s the surface eradication of crypto.