how do you cycle a tank?

Instantly Cycle Your Aquarium in One Step!
Fishless Cycling - Nitrogen Cycle Your Aquarium
A Typical Break-in Cycle Tank Syndrome

give these a look over. they'll help

 

Once you put a fish in a small amount of water, the whole situation changes dramatically. If you don't do things properly, you'll poison the fish to death. What you are trying to do is create a mini environment for the fish to live in. Obviously it is never going to be as good as in the wild, but you have to strive to make it as safe and livable as possible.

 

I have sponge filters in all my tanks but in my bigger tanks I keep an extra filter just for this purpose, when I setup a new tank i fill half the new tank with water from an established tank then fill the rest of the way with freshwater, then take one of the extra established filters from the old tank and wallah i have an established tank. been doin it for many many years and have never had any issues.

 

Yep, always keep cycled media at the ready. You never know when that urge is gonna hit to set up another tank.

If starting from scratch, I personally like to use the large prawn shrimp.

 

The big shrimp you find in fresh fishy section of your supermarket. That is, if your supermarket has a fresh seafood section.

 

Jaren that is dead shrimp for a fishless cycle which is best to do.

 

Yep, get a large shrimp, place it in some nylons and then drop it in your tank. Then watch your water parms as the cycle begins.