Starting New Tank - ideas to seed the bacteria

My son had an old 5 gallon tank he wants to put a couple fish in. I cleaned it out (no soap), and am ready to put some water in it. I have a cycled 55 gallon tank. I was wondering if it is ok to take some water and rocks from my 55 to “seed” the new tank. I don’t feel like disassembling my FX4 to get some filter media. I don’t plan to stock it any time soon.

 

Water won't do anything, and rocks will be of minimal use. The vast majority of BB live in the filter media, and that's pretty much the only thing (other than supplemental BB) that will really seed the tank. If you don't plan on stocking it any time soon, though, you're going to need to provide any BB you put into the new tank with a source of ammonia or they will die out.

 

The best would be to steal some filter media from your existing tank, but you probably know that.

My second choice ( against the advice of many on here) would to put TetraSafeStart in your filter and add 2 hardy fish. Danios or barbs and do a fish in cycle. Just check your parameters and do water changes if ammonia or nitrites get too high.

A 5 is tough.

 

Without going into the more ethical question of doing fish-in cycles, danios or barbs need a much bigger tank, so you would have to have a plan for them once the tank is cycled. If you do choose to do a fish-in, I would only add 1 fish. It's going to be extremely difficult to control ammonia in a 5 gallon with 2 fish in there.

I personally would do fishless.

 

I agree. The danios or barbs would be for cycling. Put them in your big tank and add your 5 gallon stock, a male betta?

 

I was thinking betta. I’ve never kept one, but they are pretty easy, no? I can add filter media pretty easily, just time consuming... I’ll do that this weekend. I’ll do my homework. I’ve only cycled the wrong way... overstocked and learned my lesson. Now that I’m up and running things are pretty stable. Don’t want to torture any new fish.

 

If the rock is porous, such as lava rock, it will work. You could also run a sponge filter in your old tank and move it over to the new tank.

 

I'd go with filter media that's already in the filter you have running. If you run a sponge filter in the old tank, the sponge filter is going to take weeks to build up enough BB for it to seed a new tank whereas existing filter media already has that BB built up.

Bettas are an excellent fish! Hardy and beautiful, and can do well in smaller tanks than most other types of fish (this is not to say they can survive in anything - a 2.5 gallon is an absolute minimum but you have a 5 gallon so it should be no problem).

 

Although I am a huge sponge filter addict (have one in all of my tanks). I always leave the sponge filter in a minimum of 4 weeks before using to start new tank. The quick, easy answer is to use media from your filter.

But running a sponge is great if you are gonna add more tanks in the future. Just hide it in the back. They distribute oxygen so putting it away from the main filter increases oxygen throughout the tank.