Switching filters

[keansor]

Hello! We are currently in the process of trading out filters on our 33 G. We initially had an AquaClear 30 on the tank, but decided to switch to the AquaClear 50 for better filtration, and so that my SO could take the cycled AquaClear 30 for his work aquarium (to replace a very noisy lower quality filter that came in a kit with his 10 G aquarium). We currently have both the 30 and the 50 on our 33G tank (both set to the lowest setting to keep the current under control). My question is, how do we proceed with the change over? How long do we need to keep both filters in our tank to ensure that the new one is cycled? Should we be exchanging media from the old filter to the new filter? Thanks so much for your help?

[dan2x38]

I am not sure how long to run both but I would slow the flow on the old one AC30 and increase the flow a little more on the new one AC50. I would also remove the carbon from the 50 for now this would allow more flow through your sponge & bio-max. This way you will have it populating quicker... IMO... 

[BigDaddy]

Essentially, you can set the flow on each filter to whatever you like in order to keep your tank flow "normal".  Nitrifying bacteria actually prefer very low flow environments, so even with both filters on their lowest settings, you'll still have good conditions for establishing a new colony in your new filter.

If you leave both filters on, 3 weeks is more than enough for the second filter to get a good colony of bacteria up and running.

[keansor]

Thanks for the info.

If I remove the carbon insert from the 50, should I keep it in water, or is it OK to let it dry out and than put it back in the filter when the changeover is completed? Are there any other precautions I should take? Obviously my goal is to avoid a mini cycle when we remove the AC30 that we spent so long cycling. The only additives we use in our tank are the API water conditioner for weekly water changes and Nutrafin PlantGro once a week. Will either of those harm our filter; and is there anything else we should be adding to the tank?

Many thanks.

[BigDaddy]

There's really no need to remove the carbon, but yes you can allow the carbon to dry.

Your water conditioner and plant fert will not impact the cycle.