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 !!