Fishless Cycling Advice

[Chris Wright]

I am impatiently waiting for Nitrifying bacteria to start eating. The 48litre tank at 84 degrees and high airflow from the filter top has been set up for nearly 4 weeks, eats Ammonia at about 4ppm to zero in 4 hours - and has done for about a week and a half. But the nitrites are still off the scale - instant deep purple in the test tube.

Question 1: The Interpet filter came with a plain foam and a carbon foam in it. I know the carbon impregnated part is pretty unnecessary for water clarity in a fishless cycling tank but as it's a second foam pad I assumed that nitrifying bacteria would colonate it just as in the plain foam. OR IS THE CARBON LIKELY TO SLOW OR REDUCE THE DEVELOPMENT OF NITRIFYING BACTERIA?
Question 2: I have a well established Fluval edge tank containing fish/shrimps, which will be replaced by the new tank when cycled. I could take the filter foam block out of there and cut it in half and squeeze half in alongside the Interpet foam in the new tank. This would presumably reduce the bacterial efficiency of the filter in the Edge tank a little but might speed up the cycling of the new tank. DO YOU THINK THIS IS WORTH DOING AT THIS STAGE?
I obviously don't want to jeopardize the health of the fish to do this.
Chris

 

[weezawoo]

Just to throw it in there but you could have actually taken all the media from the old tank and put it in the new filter and added the fish straight away. The media has the ability to cope with the stocking level of your current tank so you would have been ok doing that.
I don't think it would make too much difference to add half of it now as you are taking away half from the other tank!

 

[nessar]

Why dont you take the sponges from your current tank and squeeze them out directly into the new filter. Get as much gunk as you can onto it. That should give it some bacteria to start off with.

Or as already said, if you dont want to use the edge tank after, just do as many 90% water changes as needed to make sure the levels are at 0 for both ammonia and nitrite, then pop the old sponges in the new filter, add fish and TA DA! tank cycled. You can then remove the old sponges whilst replacing with new ones over time, make sure to do this very slowly though.

 

[KittyKat]

+1 above, but the problem is that the Edge's bio-media are the ceramic noodles, which probably won't fit in the new interpet filter. On the other hand, you can move the Edge filter into the new tank too, and run both filters for 6 weeks, at which point the Edge filter will be ready for removal from the new tank. If you do this, do 100% water change on the new tank, and then transfer all water and fish from the Edge, and top up with fresh, warm, dechlorinated water.

1. The carbon is long since not doing anything, it is now just a normal sponge.
2. Definitely worth it, you can move the whole sponge because the most of the bacteria in the Edge will live on the ceramic noodles (aka bio media).

Also, if your nitrite is off the scale, it can often help to do a large water change, to speed up the cycle. Use warm, dechlorinated water of the same pH as the new tank is currently at.

 

[weezawoo]

Sorry Im not familiar with the edge so wasn't sure on the filter media!!

 

[Chris Wright]

+1 above, but the problem is that the Edge's bio-media are the ceramic noodles, which probably won't fit in the new interpet filter. On the other hand, you can move the Edge filter into the new tank too, and run both filters for 6 weeks, at which point the Edge filter will be ready for removal from the new tank. If you do this, do 100% water change on the new tank, and then transfer all water and fish from the Edge, and top up with fresh, warm, dechlorinated water.

1. The carbon is long since not doing anything, it is now just a normal sponge.
2. Definitely worth it, you can move the whole sponge because the most of the bacteria in the Edge will live on the ceramic noodles (aka bio media).

Also, if your nitrite is off the scale, it can often help to do a large water change, to speed up the cycle. Use warm, dechlorinated water of the same pH as the new tank is currently at.

Thanks for the replys everyone.
I did a 50% water change a week ago but it didn't make any difference to the development of Nitrifying bacteria.
I'm adding Ammonia morning and night (from 0 back to 4ppm). I'll try moving half the sponge which will still leave some filtration in the Edge. There's no room in the Interpet for more than a thin layer of extra sponge. I already tried adding some ceramic rings from the Edge filter but there wasn't room for many squeezed in the foam and it didn't seem to help.
Cheers
Chris

 

[KittyKat]

I still think the water change could be worth it, but this time do a 90% one to get the nitrite reading as close to 0 as possible..

Morning and night is quite a lot of ammonia. Maybe the ammonia->nitrite bacteria are using up all of *something* (like a specific mineral) the nitrite->nitrate bacteria need?

 

[Chris Wright]

OK I'll add just half the ammonia amount tonight. When I checked the Nitrite tonight after adding the mature sponge half this morning, it was less than previously seen, so maybe things are improving.
Cheers
Chris

 

[Chris Wright]

Many thanks to Kitty Kat and all who replied. I brought the ammonia up to 2ppm last night instead of 4 as suggested. This morning I had less than 0.1 nitrite! It was quite a shock to see the test tube clear instead of immediately going deep purple! I'll give it a few more days and then I'm ready to swap tanks.

The move needs some project management as it's to go in the same space as the Edge tank, squeezed between a desk and a wall corner. I need to take away the brackets and shelf that the Edge tank sits on, to free up the space for the new tank and its stand. So the Edge will need to be moved complete and running, the new tank will need emptying, moving indoors from the garage, positioning, refilling and plants transferred, before transferring the fish.

Maybe I should do a full water change, add the plants and leave it to settle down in the garage before partially re-emptying and moving it?
Should I transfer any water from the Edge when I am ready to transfer the fish?
Chris

 

[KittyKat]

So the reason you had nitrite drop to almost 0 ppm after cutting ammonia in half is this: you currently have only enough nitrite->nitrate bacteria to keep up with 2ppm worth of ammonia going in. Dropping ammonia from 4 ppm to 2 ppm hasn't changed the processing speed, just allowed you to see what is actually happening. I would still advise the same precautions as with a normal cycle, including the qualifying week, unless you move the Edge filter into the new tank.

Letting a tank "settle down" after a cycle only starves the bacteria. Once you decide that you are ready to move the tank, the best option would be to drain the Edge into a bucket, move all the fish out into the same bucket (with a heater), move all the decor out, replace the tank, then put the decor, fish and water into the new tank, then top up with warm, dechlorinated, fresh water.

 

[Chris Wright]

Thanks for the suggestions. I did a 90% water change yesterday and added 2ppm ammonia in the afternoon which went to about 1.2 by last night with about 0.3 Nitrite. I added ammonia last night to bring it up to 4ppm last night and this morning there's 0 nitrite and 0 ammonia. So I guess i'm about there if its now eating 4ppm ammonia to 0 nitrite in 12 hrs. I'll follow the plan you suggested when I change the tank.
Chris