How long does it take a sponge filter to cycle?

**Greentoads41** · 07-28-2013, 06:33 PM

I have 30 gallon and 10 gallon tanks, both fully cycled and running for over 2 years. 3 weeks ago, I put 2 sponge filters in my 10 gallon, and 2 in the 30 gallon with the intent of getting them cycled so I can set up another tank. In the 30 gallon, I have 9 glowlights, 9 rummynose, 8 black neons, 1 bolivian ram. The 10 gallon is a shrimp tank.
How long does it take to get them cycled? And how do you tell if it's cycled? My plants' growth in the 30 are really taking a hit with the oxygenation that's going on, and I can't wait to get the sponge filters out of there and get the other tank up and running.
Thanks for the help! 11,000 thread in beginner freshwater, I'm so honored.

**fishmommie** · 07-28-2013, 06:54 PM

I've never personally done this but my thinking is that if you need to get them out of there for the sake of your plants, and they've been there for 3 weeks, you could move the sponge filters into your new tank, stock it lightly and see how it goes. Watch your water perimeters closely. the worst that could happen is that you might not have fully colonized media and you'd have to do some extra water changes for a while until you have enough BB established to support your new fish.

How big is the new tank, btw? that could make a difference. If it's a fairly small tank you could be fine. If it's a larger tank, you might need a little more time to grow that additional bb.

Anyone else have any thoughts?

**ijankrom** · 07-28-2013, 07:23 PM

I wouldn't think the media type would make a diiference on time it takes for the filter to be "cycled". So I think you just need to test the water and be patience. If you already have other filter on the tank it will be difficult to judge if its done. Also depending on the other filter the new filter may not contain a lot of BB since only the necesssary amount will grow for the tank.

**kim92** · 07-28-2013, 07:42 PM

They should be good to go. But it may depend on the stock in your new tank. Here is something to consider if you ever need to do this again. The sponges can be placed in a filter to get the same results as running them in a tank. If it is a HOB filter, but them in the back of it. If it is a canister filter, open it up and put them on the top. That will get you the same results as running them with an air pump in the tank.

**Betta113** · 07-28-2013, 08:11 PM

It might be better to put all your extra sponge filters in the 30 gallon tank. Shrimp have a very low bioload, so the bacteria that would colonize in the 10 gallon would be very low and only be able to support either another shrimp tank or maybe a single betta.

**Rocksor** · 07-28-2013, 09:18 PM

If the filters on your 10g kept ammonia and nitrites at 0ppm, then there will be minimal bacteria in the sponge filters. Ammonia and nitrite would have to increase a little to seed the sponge filters with both ammonia and nitrite eating bacteria.

Why not just do a fishless cycle on the 30g?

**Greentoads41** · 07-29-2013, 03:50 AM

They should be good to go. But it may depend on the stock in your new tank. Here is something to consider if you ever need to do this again. The sponges can be placed in a filter to get the same results as running them in a tank. If it is a HOB filter, but them in the back of it. If it is a canister filter, open it up and put them on the top. That will get you the same results as running them with an air pump in the tank.

That's a good tip, thanks.

How big is the new tank, btw?

It's a 15 gal, and I don't plan on a heavy stock. Don't laugh at me, but I want to try breeding.

Also depending on the other filter the new filter may not contain a lot of BB since only the necesssary amount will grow for the tank

I hadn't considered that, so there might not be a lot of bb growing in the sponge filters? Since the other 2 filters in the tank are an aqueon 30 and an aquaclear 50.

It might be better to put all your extra sponge filters in the 30 gallon tank. Shrimp have a very low bioload, so the bacteria that would colonize in the 10 gallon would be very low and only be able to support either another shrimp tank or maybe a single betta

Good point.

Why not just do a fishless cycle on the 30g?

Because it's already cycled (face palm)

**mommy1** · 07-29-2013, 04:00 AM

Set up the tank and put the sponge filters in it along with 1-2ppm ammonia (depending on the size of the tank). If you have 0ppm ammonia and nitrites and some nitrates within 24 hours you know the filters are cycled. If not, then continue on with a fishless cycle in the new tank, it shouldn't take long since the sponge filters have been used for 3 weeks.

**Greentoads41** · 07-29-2013, 04:12 AM

Thanks, I think that's the way to go.

**Greentoads41** · 08-01-2013, 03:03 AM

Yesterday, I put the sponge filters into the new tank. I then put new water into the new tank (comes out around .75 amonnia) with a couple shiners from my pond. Today I tested the water, and lots of ammonia was still present, with no2 at 0 and no3 at 0. I think I'll do a fishless cycle then lol