Hi, some advice please?

[ganaM]

I'm setting up a new tank and wanted some advice on cycling chemical readings please:

I've been setting up a bigger tank for the first time, conducting a fishless cycle without ammonia as I believe I can't obtain it is Australia? So I used fish flakes. To start, I conditioned the water and added API quickstart bacteria to the 165 litre tank. I also added my healthy tank substrate and some filter substrate from my healthy 90 litre tank - I didn't want to use that filter as that tank has fish in it. As ammonia is a controlled substance I started adding fish food every 12 hours. I've had some odd readings so could someone assist interpretation please?

I think the results may be due to adding API Quickstart which has resulted in 0 ammonia readings? By day 4, I had Nitrite readings but no ammonia, which spiked for 2 days then dropped to 0.

Is it possible my filter media has almost instantly cycled the tank or am I doing something wrong? I haven't done nitrate readings yet - should I start doing them ?

These are my readings:
From Day 1 to Day 3 = Ammonia 0 & Nitrite - 0
Day 4 = Ammonia 0 & Nitrite - 0.25
Day 5 = Ammonia 0 & Nitrite 0.5
Day 6 = Ammonia 0 & Nitrite 0.5
Day 7 = Ammonia 0 & Nitrite 0

Thanks so much, I really appreciate the time you have taken to read this message and reply !!

[Bettarazzi]

Hi ganaM. I think the problem is that the fish food doesn’t break down in a controlled way. But I would expect a week to be about right for a tank to cycle. Using substrate and filter media from established tanks will also have sped up the process. Check the nitrates. I think you’ll find you’re good to go. Of course things can change once you add fish. So I would continue taking readings and doing partial water changes after the fish are added. What species of fish will you be adding?

[shadoh]

Hi ganaM
Welcome to the forum.
It sounds like you aren't too far off from being cycled.  As Bettarazzi mentioned - your readings will probably change once you introduce fish.  Depending on the tanks size and number of fish you are adding, I personally wouldn't add all your fish at once, but do it gradually over a week or two while keeping an eye on your parameters and staying on top of waterchanges.  

Can't wait to see what your tank looks like once you have it completed with fish in it!