Filter Change

Quick question on filter changes. I have the Top Fin 20 filter (pic attached). The red circuit shows where water is over flowing back into tank. When I do water changes once/week I take the filter out and rinse it off, this used to help but no longer. Tank if fully cycled and has fish.

How do I change this filter out with completely removing all the good bacteria and throwing my tank into another cycle?

you need to fully transfer the media from the old filter to the new. You could also try running new and old at the same time. For the duration of the transition I would be checking the chemistry each day as if you were cycling - that way nothing bad can sneak up on you

Miles_hot said:

you need to fully transfer the media from the old filter to the new. You could also try running new and old at the same time. For the duration of the transition I would be checking the chemistry each day as if you were cycling - that way nothing bad can sneak up on you

Click to expand...

So here is what I did, I bought replacement filters and completely changed the filter media out (having both the old and new in the filter not an option, filters too small).

I then shook out the old filter in tank water (in bucket I use for water changes) to get rid of the some solid gunk then lightly shook it out in the tank with the new cotton filter/new carbon running and left the old filter at the bottom of the tank.

Is this a viable way of doing this change? If so any recommendations on how long to leave the old filter in the tank?
Tanks been running ~6 weeks now.

The old filter media needs to be in the filter itself. I was in a similar situation, and basically just stuffed the old filter media into the filter kind of behind the new filter media. If you take the bag off the frame it's on it works.

You shouldn't be using carbon in your filter unless you're trying to filter out medications given.

The way you've done it, unfortunately you just started the cycle over from scratch.

I think I remember GVG talking about his HOB backing up and what he had to do to get it to flow right again. Maybe he'll come along and see this, or perhaps there were some other members who have experienced this. In my own case, squeezing out the sponges and swishing the loose media and cleaning the plastic media holding basket have always resulted in a normal water flow, at least from my AquaClear HOBs.

~~waterdrop~~