crud from rinsing filters...

Dirty. Its looks like the toilet when you are sick : I dont even like too look at it.

Opaque brownish-black. Pretty gross to think of it as a bucket full of fish poop...

Sam

Yep if you ever saw the movie back to the future 3 it is like the drinking water from the old west... Brown...

My rule of thimb on sponges is that the third rinse should be clear, clean or nearly clean water. If it needs more than 3 rinses, then I need to maintain the filter more often or to have more filtration. Either option can do the job.

All JMHO and IME, YMMV.

BTW, the dirty stuff from rinsing filters is called "mulm" and is great for starting up new planted tanks - well mineralized nutrient mixture which will add to tne base layer of your new substrate. If the material is fresh, it will assist in avoiding cloudy water outbreaks in the new tank. It has live heterotrophic bacteria to help establish the needed complement of mixed buggs in our tanks.

I just cleaned mine looks dark brown with stuff floating in it very nasty ofcourse thats from both of the filter medias from my emp400 and my filter sponge from my bio-wheel Yummy!!


p.s. not as bad as my mothers 3 tanks 2X 10 1X 29 uses these little tiny garbage rio filters and shes never cleans them out but the cuppys she breeds in the 39 just love that nasty tank the krin and rams in 1 10 hate it and the tetras in the second ten look like s**t but i also went all the way to her place today to clean them up and balance the water her rinse bucket looked jet black ick!

SEE ATTACHMENT FOR HER
PH
AMMONIA
NITRITE
NITRATE