View Full Version : 10-27g cycling question

03-28-2007, 06:40 PM
Ok, here's the situation.

I have a planted 10g. I have an empty 27g tall. I am taking down the 10g and putting the 27g in it's place. If I use all the water from the 10g in the new tank as well as the gravel and filter, how badly do you think it will shock the tank. I want to do a full switch if possible. I have 6 young Kribensis coming in the next day or so and need the room for them. Any ideas if it will work or not?

03-28-2007, 07:17 PM
Not sure how big the kribs are or how dirty they are, but your 10g currently has the bacteria population designed to support the bioload of 10g worth of fish. If the 10g wouldn't be able to support 6 kribs (which I don't believe it will), then the bacteria population from it won't be able to support 6 kribs in the 29g, so you'll probably see a small spike, depending on how heavily stocked the 10g is

03-28-2007, 08:28 PM
I have a filter for a 55g going on the 10g, so I think the tank cane handle a bit more then a 10g bioload. The Kribs will be young, about a month or so old. I don't assume they would be too much of a strain. I am more concerned about adding 17g of water to the tank. It would be like doing a 2/3's water change on the 27g. If I do some small water changes (10%) every day till the cycle catches up, will I be ok?

03-28-2007, 10:56 PM
The bacteria is in the gravel and filter, so adding new water does not really do much, if anything, hence why you don't see an ammonia spike after a 50% water change. Put all the gravel and mulm (the brown crud at the bottom) and let it settle a bit with just a minimal amount of water in the tank (enough to cover it), then add water very slowly so nothing gets churned up. The tank should be ready (as ready as it can be) for fish in a few days. Until then, I would add some ammonia to keep the bacteria population up. As for how much, I'm not sure, but you can basically multiply however many drops it took for the 10g by 2 or 3. Since you already have both types of bacteria, the tank should recycle in no time.

And what I mean by the 10g thing is that, regardless of how big a filter you have, you only have enough bacteria as is required to process 10g worth of fish. More bacteria will need to grow to cope with a larger tank with a larger bioload.

03-28-2007, 11:29 PM
I had no way to do change over in stages. Most of the fish I have are hardy (except the sparkling gourami). I have stepped up the aeration. I will wait a few days (if I can) before adding the Kribs. The danios are doing fine and I don't see any signs of stress, other then from the move itself. Other then the water being a bit cloudy, things are going great. I used the same method for moving my fish from a 33g to a 55g. I didn't loose any fish. I know it's a risk, but as I said, I had no way to set up the tank first.

03-28-2007, 11:36 PM
Ah, kk I see your point. Good luck!

03-29-2007, 11:36 AM
You should be fine.....I have changed over 4 tanks from gravel to sand now and all I left in there was a small mesh bag of the old gravel for 2 weeks to help boost things along. I realize that alot of my bacteria was in my filter, but alot is in the gravel also and even though I removed alot of the gravel over a few weeks, there was still plenty in there the day I did the change over and I haven't seen any spikes. Once the bacteria is established it catches up pretty easily.
I am understanding that you moved everything from existing 10 gal to a new 27 gallon tank, gravel, decor, fish, filter, etc. Not only do you already have a cycled (although a little delicate) tank, IMO you should be fine adding 6 small kribs. You have almost 3X the amount of water to dilute the added waste, just check your water parameters daily to make sure you aren't getting any small spikes, and if you do, you know how to handle them.
Good luck and enjoy your kribs, they are beautiful!

03-29-2007, 12:08 PM
Everything from the 10g is in the 27g. Filter, heater, plants (live and fake), rocks, gravel, ornaments, driftwood and fish. The fish are doing fine, no signs of stress. I am letting the temp drop slowly from 80 to 77F, as the Kribs don't do so well at 80.
The woman I am getting the Kribs from is dropping them off this evening. She wrote me to say I may not be able to have 6, but will get at least 4. She said that some of them are too small to sex, so I am figuring they are about

<-------> <---That long.

I would like to have 1 or 2 males and a group of females, but I will be happy with any. The LFS sells them 2 for $14, so if I get a group that doesn't work, I can add to the group or trade them out for ones that do.

Now I am just figuring out how stocked my tank will be and if I can add more fish, like more danios and an albino Bristlenose (they are so cute).

03-29-2007, 01:09 PM

Any excess ammonia and nitrite not taken up by the bacteria will be used by your live plants. When you add your Kribs, the plants will also take up some of their bioload. You may still have a small ammonia or nitrite spike, however. Just keep an eye on it for the first few days and you should be fine.

Congrats on the bigger tank and the new arrivals.

03-29-2007, 01:22 PM
Thanks. I am pacing like an expectant parent :). 4:30 is taking forever!

03-29-2007, 03:59 PM
Nevermind, just read up on kribs and they are such small fish that I do not think it will be any issue. I was thinking they were similar to african cichlids in size, LOL.

03-29-2007, 05:12 PM
I had 6 Kribs ion a 33g with tons of other fish. I think I has 2 young parrots, a pearl gourami, 2 dwarf gouramis, a molly, a common pleco and 4 weather loaches. I know the problem won't be with the tank size as far as their size, it will be the aggression level.