medicines harmful to nitrifying bacteria

[skoda]

i understand that prazi and methylene blue is harmful to nitrifying bacteria. are the following med. also harmful ?

formalin, malachite green, dylox, metro (i heard this will induce bacteria blooming?), fenbendazole, potassium permanganate, nitrofurazone and furazolidone.

thks,
skoda

[fcdiscus]

Prazi is not. Meth blue at heavy dose may be. Formalin at higher dose is. Mal Green is. Metro and dylox are not. Fen should only go in food. Pot Perm is. Other two only if overdosed. Frank

[brewmaster15]

I agree with Frank. The only add on is that Metro will not directly harm the bio filter, it only works on a small number of anaerobic bacteria (non-oxygen using)... but it has a sugar base, so you can get a bacterial bloom... this will use up oxygen, and can harm both fish and biofilter...
...The solution... heavy water changes between doses, and additional aeration.

hth,
al

[skoda]

thanks for the info., so i should clean the bio-filter whenever med. is used.

i have a bio-sponge filter and tank top mechanical filter in my main tank.

my question is can i still run the mechanical filter (w/o activated carbon, just the sponge)?

[Ardan]

hI,
Run the sponge, some bio activity remains in the filter. Whatever is impaired from meds usually rejuvenates quickly.

hth