Im running two Eheim Ecco 2232 on a 20 Long. Originally they were on two separate 20 Longs. Without going into the boring details, they are now running in tandem on the same tank. I suppose too much filtration is better than not enough.
I just did the cleaning and maintenance on the other one today. I usually like to stagger the cleanings by 2-3 weeks to make sure things stay stable. After seeing the "fog machine" go off, I'm going go ahead and do it next week.
I do have some flexible brushes that I use for the pipes and tubing. I was amazed how much flow I got back after using them the first time. That build up in the tubes has more effect than some people think.
Anyways, I was just taken back at how much gunk was blasting out. Ive never had that happen before.
Im not even sure how/why its gotten that dirty. The tank itself isn't overstocked and I try not to overfeed (try being the operative word). I usually clean them out every 2-3 months, but if Im being honest I cant actually say how long its been.
Too long, apparently.