New Fluval fx4 question with old filters

I just got a fluval fx4 and about to move fish from a 40g breeder to a 125 gallon that currently has a couple of HOB aquaclears.. can I just put the sponges from the aquaclears in the center of the fx4 with the ceramic rings for it to be instantly cycled? Or should I just run the aquaclears for awhile as well.

 

Can you replace some of the white sponges with the Aquaclear sponges?

 

Either way will work. You can run the hob in addition for a few weeks while the fx4 gets seeded. Otherwise if putting the old media will Work well also.

My only suggestion if your going to use the center tray and mix the foam with the bio rings would be the cut the sponge up into one inch cubes so it mixes a little better with the rings. If you just place the foam blocks in the trays and then place the bio rings around them, chances are water will end up bypassing the sponges by taking the path of least resistance. This is probably overthinking in my part, but just a suggestion!

 

Can you replace some of the white sponges with the Aquaclear sponges?

I don't believe so it looks kind of like a special round one? Not sure though

Either way will work. You can run the hob in addition for a few weeks while the fx4 gets seeded. Otherwise if putting the old media will Work well also.

My only suggestion if your going to use the center tray and mix the foam with the bio rings would be the cut the sponge up into one inch cubes so it mixes a little better with the rings. If you just place the foam blocks in the trays and then place the bio rings around them, chances are water will end up bypassing the sponges by taking the path of least resistance. This is probably overthinking in my part, but just a suggestion!

I could def cut the sponges up and place them in there

 

Yes if you remove one of the sponges from the fx4 and squeeze the aqua clear sponges into that space you should be fine with the existing fish. Add new fish slowly and not all at once. Keep the 40 and use it to qt new fish. Now the fx4 may not be enough for the 125. I’m using an fx6 for around 3 yrs and I’m backing it up with a wet/dry and a internal filter. My tank is well stocked. But you’d think an fx6 would be enough. If you havnt bought the fx4 I’d advise a wet/dry or a sump. Either will be much better filtration.

 

Yes if you remove one of the sponges from the fx4 and squeeze the aqua clear sponges into that space you should be fine with the existing fish. Add new fish slowly and not all at once. Keep the 40 and use it to qt new fish. Now the fx4 may not be enough for the 125. I’m using an fx6 for around 3 yrs and I’m backing it up with a wet/dry and a internal filter. My tank is well stocked. But you’d think an fx6 would be enough. If you havnt bought the fx4 I’d advise a wet/dry or a sump. Either will be much better filtration.

I already have the fx4 i figured it would be enough since the box said up to 250 (which i know they always say way higher than its actually good for) but i figured since 125 was half of 250 it would be ok. I guess I can just add a few larger HOB or something if I need more I guess, and dont plan to add any fish for awhile after I move the old fish over, gonna let the tank settle in for a month or something

 

A cheap
backup i use.

 

A cheap backup i use.

Thanks! Will look into these

 

I just got a fluval fx4 and about to move fish from a 40g breeder to a 125 gallon that currently has a couple of HOB aquaclears.. can I just put the sponges from the aquaclears in the center of the fx4 with the ceramic rings for it to be instantly cycled? Or should I just run the aquaclears for awhile as well.

Considering the nature of the FX4 I'd reserve the filter cores for biological and specialty mats (one's that are cut to purpose). Leaving both of your HOB's in for the time being seems the natural choice. Leaving the mechanical outer ring as designed is a good idea as well.