Question on using old filter on new, larger tank

[Kilgore]

Hello,

Does anyone think I can get away with using my Eheim Ecco 2231 (rated for up to 30-gallons) on my new 46-gallon tank, at least until I can afford the new filter? I currently have a 25-gallon with 30 fishes, all under 2 inches, who are ready to be moved to larger quarters. Unfortunately, I can't afford the larger filter until later. Logic tells me that if I move the exact same fish into the bigger tank with the same filter, I can avoid new tank syndrome, and everyone should be better off due to the larger water volume.

That said, the substrate will be new, and the water won't be filtered as many times per hour. Also, the current very high stocking level of plants will be not so high in a bigger tank. So what are your thoughts? What are my options? And, later, if I buy the Filstar for XP1, can or should I also run the Eheim? Or would that be too much filtration for the plants?

Thanks!

 

[Musket]

I would run the 2 together for awhile to help seed the new filter, can't you lower the flow on those filters? If you can, you could set both to a lower setting and that shouldn't bother the plants too much.
I would say you can run the smaller filter on the bigger tank for awhile and get away with it. You may have to do extra water changes though. Definitely keep at least most of the old filter media in the Eheim to keep the bacteria so it will help cycle the tank. Use all the plants, that will help too. I'd go get a package of Bio-Spira to make sure to avoid new tank syndrome. Hate to lose babies just because we need to give them a bigger home. I used a bio-spira on my 46 even though a had a preseeded filter running, plants, rocks and gravel from the old tank,. The extra $11 was well worth the peace of mind.
Good luck

 

[Fishyfanatic]

You should be fine for a while. Keep monitoring your levels to check for any abnormalities. Once you do purchase the new filter, run them at the same time for at least 2 weeks.

 

[severum mama]

The BioSpira wouldn't hurt of course, but I really don't think it will be necessary. I've cycled new tank in days with less. Just keep your test kit handy and be prepared to change some water if necessary. I agree with Fishy, run the new filter with the old for a couple weeks and you'll be fine. Good luck!!

 

[TomK2]

I think that you would be fine with the smaller filter on the larger tank, provided you don't increase the fish load. The ammonia and nitrite will be diffused in the water, so that the little filter will get it all. However, if the little filters flow is too little for the tank, you can expect less particulate filtration and more debris settling in the substrate. Then later, when you have the larger filter, run the old and new filter simultaneously for several weeks. Then you can withdraw the old filter, and start adding fish. I don't see too much filtration harming plants unless water flow is excessive (hard to do?) or surface agitation too much for a CO2 injected tank.

When withdrawing the old filter, if you have seperate biomedia compartments, you can take media out gradually if you are worried about a loss of biologic activity. But if you wait 4 to 6 weeks, I am confident that a sudden withdrawal will not be an issue. I am conserative with these estimates, so that it probably can be done faster.

 

[Kilgore]

Thanks everyone for the great replies. I don't tend to change any media on the old filter and in fact I plan to just move it right over so that it is disconnected for as brief a time as possible. I will definitely run the new filter concurrently as soon as I can afford it. I plan to add some new plants also and they will hopefully help to ease any spikes that may occur due to the loss of bacteria on the glass and substrate.

One interesting thing I read about the Eheims is that they are rated based on the water flow when they are full of media, while most other filters are rated empty. Meaning that in theory the Eheim could be rated for a larger tank if it were rated the same as other filters.

I can't wait to get everything set up and see how much the fishies love their new, roomy home.