Topic: Thinking about a cannister

[Boven]

On both my 38g and 20g aquariums I've got HOB filters, which are doing a good enough job of keeping things clean.  However, lately I've been considering putting a canister on my 38.  While the Aquaclear HOB on it seems to be performing well enough, it makes a bit of noise.  I've checked and cleaned the impeller and all seems to be working properly.  The filter's cover amplifies the sound making it a little noticeable.

While I can live with it, I've had thoughts about swapping to a canister, probably something like an Eheim 2234.  The questions that spring to mind, though, is how long I would need to run the filters in tandem and how would I know when the new filter is 'ready.'  Obviously I'd need to leave the HOB on until  a canister was able to get a good population of bacteria going.  Since it's cycled tank, I figure I could use some media from the HOB to help get the canister started.  Is there any way to tell when the canister was actually able to support the cycle without just shutting down the HOB and testing the water daily?

[Ppulcher]

My HOB filter rattle the lid a little bit, too.  I think that is the source of the noise. 

If I were doing a HOB to canister switchover, I would probably use some of the media from the seasoned filter to seed the new one, turn down the flow of the HOB to minimum and run them in tandem for 3 or 4 weeks.  For insurance, you could always put the HOB on the other tank for a little while and monitor the water in the tank with the new canister.

[Cholly]

For insurance, you could always put the HOB on the other tank for a little while and monitor the water in the tank with the new canister.

Great idea!

[IslandHopper]

I recently switched both my tanks to canisters... I simply removed the "cartridge" from my HOBs, cut it open and dumped the charcoal out, then just crammed the floss from the old filter cartridge into the bottom tray of the canister.  I removed the HOBs at the same time I installed the canisters... and had NO spikes for ammonia or nitrites.
The old filter media being on the bottom, should allow the ceramic pellets above it (downstream) to fill with bacteria in short order.  I figure I'll let em run for a month or so, then open them up and remove the old filter material and replace it from the big bag of floss I got from the fabric store.

In any case... if you transfer some of the old media, you should have NO cycle issues.