# Seeding new tank with old water



## geekee (Jun 12, 2010)

Hi all. I have gotten a 55 gallon aquarium in which I plan to plant semi heavily and add tetras and the like. I currently have a 20 gallon aquarium with a blind cave tetra in it that is currently 9 years old. I cannot keep both tanks so sadly the 20 will have to go. If I set up my 55 and place all of the water in the 20 into the 55 and then fill the tank up with new water will it be enough to cycle the tank quickly? Hopefully the 20 gallon tank water is enough to seed the new 55. He has lived well past the average 5 years for this species and I have grown to be very attatched to him. Any information on the subject will be very much appreciated. Thanks all.


----------



## matt11390 (Feb 17, 2010)

You shouldn't have any problem with your idea. It will make for a rapid transition to your 55. I have done this many times and it works well. Just make sure the water from your 20 is disease free and has had a water change within the week of changing to the 55. Depending on how much space in the 55 you take up with substrate and plants you may not even need to use the entire 20 gallons from your old tank. At least shoot for 30% - 40% of old water to new water. This isn't a magical number I just usually do a 60% - 70% water change weekly and never had any problems. Have fun.


----------



## ddavila06 (Jan 31, 2009)

i second matt, but i always used all the water in my smaller tanks and tried to use the same filter as well and didn't loose a single fish that way


----------



## bosmahe1 (May 14, 2005)

In addition, run the uncleaned filter from the 20 on the 55 for a week or so. If you are transferring the gravel, that helps too.


----------



## tuffgong (May 21, 2010)

Most of the good bacteria is on the hard surfaces in your tank and in your filter media. Transferring the water can't hurt but not nearly as beneficial as transferring the old filter/filter media and the old substrate.


----------



## geekee (Jun 12, 2010)

Thank you all very much for your replies they are very helpful. I will transfer some of the old water as well as run the old filter on the new tank for about a week. I also plan to take some small mesh type bags and fill them with some gravel from my twenty gallon tank and place them in the 55 until the 2 Aquaclear 110s (I know... way overfiltered) have been fully seeded. Thanks again for all of your information. This is an excellent forum.


----------



## tuffgong (May 21, 2010)

Overfiltered? What's that?? I think that's against the planted tank religion. You can never have too much filtration!!


----------



## Cliff Mayes (Jan 29, 2007)

Filters provide water movement and sometimes filtration. Not all tanks need filters but anything has a lifespan and will fail, not if but when, so using more than one filter is just plain smart. The comment about never having too much filtration is right on.

Bacteria exist on something, not in water. If bacteria are not fed regularly they die back. If you put the filter on the new tank move some fish and feed them so that the bacteria have something to eat. Being in a tank for days with no food is not good for the bacteria.


----------



## geekee (Jun 12, 2010)

I will replace the carbon bags with purigen filled bags as I have heard that the carbon strips the plants of nutrients in the tank. Are there any other recommedations for modifications to these filters? Thanks again for all the help. I am learning a ton.


----------



## JanS (Apr 14, 2004)

Cliff Mayes said:


> Bacteria exist on something, not in water. If bacteria are not fed regularly they die back. If you put the filter on the new tank move some fish and feed them so that the bacteria have something to eat. Being in a tank for days with no food is not good for the bacteria.


I agree, timing is everything so if you don't add something to feed the bacteria right from the start your efforts will be worthless. 
Good luck with it and let us know how it goes.


----------



## Diana K (Dec 20, 2007)

Without fish in the new tank, add ammonia and do the fishless cycle. 

If the only fish is the Blind Cave Tetra, then that is all the bacteria there will be in the tank: Enough to handle the waste from this one fish. 
When you are ready to add more fish you will have to add more bacteria. 

a) Grow it yourself with the fishless cycle. 
b) Heavily plant the tank, and the plants are your biofilter. 
c) Add Nitrospiros bacteria. Read the label. All other 'bacteria in a bottle' products have the wrong species. Microbe Lift's Nite Out II, Dr. Tim's One and Only, Tetra Safe Start are the three that have the right bacteria. 

There is so little bacteria in the water that it is not worth saving. There may be other reasons to save and reuse the water, but not as a source of nitrifying bacteria. 
Keep the old filter running on the new tank, or move the filter media to the new filters. It takes longer than a week for new filter media to grow a big population of bacteria.


----------

