Just from my experience when my girlfriend put 5 goldfish in a 10 gallon tank
, the ammonia spiked insanely off the charts...
I went out bought (3 weeks ago) an AC20 put the ammonia media filter with charcoal, bio-max, and sponge in the AC20 HOB
I removed about 4 gallons, in 18 hours the water was (and still is) crystal clear and the ammonia (just checked it) is at 0.25 ppm
. Yes ideally it should be 0; however she put 5
in a 10 gallon ......... One she has had for 7 years living is a 3 gallon bowl, now he is in the tank...
Just throwing that out there