View Full Version : Gunk on the filter pad

01-08-2019, 06:32 PM
Hello everyone. I have a 35 gallon tank which has been set up for over a year. I have one goldfish and two algae eaters, no plants since the fish eat them. My question is why do I have so much brown gunk on the filter? I have to wash it every day or it gets clogged so the water goes over the overflow. The filter is for a forty gallon tank. I only feed the fish every other day and then only a small pinch of flakes, Any idea how to control the gunk and why there is so much of it? The tank sits in a corner away from any windows and had a light made for the tank that is on all day-off at night.

01-08-2019, 06:38 PM
Hello , welcome aboard. I hope you will enjoy the forum.

01-08-2019, 07:38 PM
You need to do more cleaning of the substrate with a gravel vacuum, like 3 times a week for 15-20 minutes. Once your substrate is barely a brown color for every square inch, you will find that there will be less gunk build up in your filter. The gunk is organic material, and more likely a collection of fish waste from too much feeding in the past and not enough substate vacuuming.

01-09-2019, 12:52 AM
Welcome to the AC

What kind of filter, and what do you mean by "filter pad"?

Is it on the outside or inside of the filter?

01-09-2019, 02:30 AM
The gunk is also a buildup of the bacterial wastes-isn't it? That tank has a very high bioload, you may want to invest in a second filter or a filter for something like a 75 gallon tank. What type of goldfish do you have?

Oh my, where are my manners; :welcomeconfetti: to AC :wavegreen:

01-09-2019, 09:50 AM
Welcome to the AC... :22:

01-09-2019, 03:45 PM
Welcome to the AC

01-09-2019, 05:10 PM
Yes! Welcome to the AC!
Removing organic wastes should help with the brown gunk. It might take a while to see an improvement, but slowly you should. Boundava made a good point, it's a lot of bioload for a 35g, especially depending on the species of 'algae eater' and goldfish and size of fish. Have you tested nitrates lately?

01-11-2019, 02:57 AM
Welcome aboard ;-)

01-25-2019, 01:44 PM
welcome to the AC some brown gunk would be normal but if it is clogging the filter then something needs to be done. please follow the advice from others on this post. BTW if you are washing your filter pad in tap water every other day there is a good chance you are killing off some of the beneficial bacteria. there are some great articles on here covering the subject of biological filtration. keep at it.