is my cycle done?

Ammonia is down to Zero (been there for a few days now), nitites have never registered above Zero, Nitrates are just starting to register. sounds like its done to me, but the Nitrites never spiked.

I was going to add a few fish this weekend but the missing nitrites has me a little worried.

what do you think?

is my nitrite test inacurate, or is there another reason?

Doug

Are you doing a fishless cycle?

http://www.thetropicaltank.co.uk/cycling.htm

You wont see nitrites if your not adding something to the tank (either via fish or by manually adding some form of food) to feed the bacteria.

How long has the tank been setup? If it has been less than a couple of weeks I wouldn't consider adding any thing other than 1 or 2 hardy fish to feed the cycle.

If you have a mature filter running on the tank you might have completely missed the cycle?

setup around two and a half weeks ago. I have been using "Cycle" and added old water from my other tank aswell as rinsing the old filter catridge in the new tank.

been feeding fish food into the tank since day one, only done one small water change, ammonia got as high as 1.0ppm then gradually came down to Zero.

not doing fishless cycle as I dont have any pure ammonia, although figured feeding the tank would be simmilar just take a little longer.

Doug

I don't know much about your method as I have never tried it. I cycle new tanks by adding the new filter to an old tank for a few weeks.

If I add a new filter to a stable tank without a filter, would it cause a cycle?

If you mean will it cause a cycle in the stable tank - then no. If the tank has been set up and running with fish etc for some time then it will be fully cycled. A filter is not a necessity but very helpful. All it will do is create bacteria in the new filter which, once established, can then be moved to a new tank.

If you have plants in the tank they will be using up the nitrate and it will have cycled and you can start adding fish slowly.

Yeah - make sure you try to hold yourself back

It's easy to add fish *way* too fast - they all look so lovely in the shop, and they obviously need you to take them home...

tell us some more about your tank?

added old water from my other tank

In my experience having added old water from a tank that is already set up would limit the amount of time significantly for the new tank to cycle (depending on how much water came from the old tank).

When I set up my 4 ft tank(280litre approx) I took about 50 litres of water from a smaller tank I have and had that running with no fish but with plants and "cycle" for about 3-4 weeks and then started adding fish and I didn't lose any fish and had no probs with the water.

All the best with your tank, what fish are you thinking about having?

kool thanks for the info guys.

I will go to the LFS tommorow after work and pick up a couple dannios, 3 this time 3 in a week or so depending on how the water reacts.

I've got a thread up about my tank over here:

http://www.fnzas.org.nz/fishroom/1-vt14831.html?start=0

includes info about planned fish.

thanks again for the info, case closed

Doug

In my experience having added old water from a tank that is already set up would limit the amount of time significantly for the new tank to cycle (depending on how much water came from the old tank).

When I set up my 4 ft tank(280litre approx) I took about 50 litres of water from a smaller tank I have and had that running with no fish but with plants and "cycle" for about 3-4 weeks and then started adding fish and I didn't lose any fish and had no probs with the water.

All the best with your tank, what fish are you thinking about having?

Water doesn't really contain many bacteria compared to surfaces in the tank (gravel, filter meda etc) It wont hurt to add the water but it wont help the cycle very much if at all, sorry. You would be far beter to take a few cups fulls of gravel and grunk from a setup tank and dump it in the new one. Or even better run the new filter in the old tank for a couple of weeks.