Coffey5030

how long should I leave the old filter in when making the change to a new one?

AlyeskaGirl

I'd leave it running for a month or more so the new filter has a chance to seed. I got a new filter about two months ago, but never did take the other off. lol

CWO4GUNNER

Wow! Good filter or should I say $$, makes me feel better about wanting to splurge $90 on a new 350 magnum for a backup (just kidding) I don't have a clue what your media configuration is but I recommend cleaning what is reusable in aquarium water by squeezing and rinsing and then replace just a portion with new media so that you don't go through a mini cycle due to lowered beneficial bacteria that is tossed out or cleaned with tap water (a killer).

Coffey5030

From the 2 months of research I've done, the 2126 was the way to go. I did however, add much of the media from the old filter to the canister. I was thinking of taking the other h.o.b. out next Friday. This may be a slight risky but, from what I have come to understand these beneficial bacteria can multiply by orders of magnitude in 24 hours! surely they can seed the new filter in a week.

Dozey

IMO I would reconsider that decision. Yes bacteria does multiply quickly but only if there is a food source. Since your current filter and décor already supports the bacteria required to deal with the current bio-load in your aquarium there really isn’t any excess food to promote new bacteria growth in your new filter. Bacteria will cover all surfaces in your aquarium and eventually in your new filter but it will take time.

Even after an extended period of time bacteria will be evenly distributed over all surfaces of your aquarium. So to keep things simple lets say you run your new filter for 2 month and it becomes part of the surface area and bacteria is evenly distributed. 33.3% bacteria are distributed on the gravel and décor. 33.3% of bacteria are distributed on the old filter and the remaining 33.3% are distributed on the new filter. Removing the old filter will remove 33.3% of the distributed bacteria and therefore there is 33.3% less bacteria to deal with the bio-load of the aquarium. You can expect a mini-cycle at this point.

CWO4GUNNER

It a all a matter of what works for you and unfortunately you are not going to find that out until you experiment which is unavoidable. My basic rule when it comes to fiber media, wool, sponge, cellulose exc is if its reusable don't replace it just clean it in aqua water. If its carbon or resin I rinse half and replace half in net stockings. But no matter what it is if its wasted and filthy like matted black angle hair or wool, I toss it out and replace it as chances are there is not organism living in it. Just use common sense and dont use tap water on whatever your going to reuse. But if everything is working fine otherwise giving you no indication to go in there avoid it. Valid indicators would be low return flow, noticing when you turn your filter off then on againe huge blooms of waste come out for a few second (not a tiny bit) or the initial smell from the out flow when turning the filter back on is awful, or you have an unexplained ammonia spike that a water change cannot put a dent in. These are all indicators that you need to get in there and clean house and since your going in there anyway might as well be thorough and take the filter completely apart cleaning the tubes, impeller housing and any reusable filter media. Remember when clening always use up to 3 buckets of aquarium water and priming, DO NOT use tap water here.

Coffey5030

Ok. I will hold off on taking the old filter out. Better to be on the safe side I guess.