Eheim 2026 ??

Try tilting it from side to side. This should release any trapped air in the head. I would leave the whisper run longer than a couple of days, like about four weeks to be sure the 2026 is established.

I agree, four weeks is a minimum. The bubbles should cease within several days.

Jim

it takes a while for the bio media to get started in the new filter, you can speed it up with putting the media in the whisper into the cannister. its just the white bags rights?

The bubbles are a normal occurence when setting up a new Eheim, I have a 2028, and after setting it up for the first time, I noticed that there were air bubbles as well. It can take anywhere from a few hours to a couple of days to get rid of the air, depending on how much is still trapped in the canister.

As for the other filter, I agree with everyone else, it'll take ~ 4 weeks for the bacteria to become established in the new 2026.

disagree with 4 weeks

I disagree with the 4 weeks, like blitzen25bm said, just take the bag off the Whisper and put it inside the Eheim. There, done, you just moved the bacteria.

Take out some of the media in the lower basket to make room, and be certain that you remove more than enough for if you overpack these baskets they will warp and not fit right (been there, done that).

So, take a lot of the noodles out of the lower basket, add the whisper bag, turn it all on again and wait about a week or so. The upper media in the Eheim will have a lot of bacteria on it now, because of the high flow rate and the fact that the old media is just upstream of the new media. So you can remove the Whisper bag at one week or later, whatever works for you, you could even let it go for a couple of months until you want to check to see if the filter needs cleaning.