Hi Eco. Sorry to bother you with another fishless cycle question but I am a little bit stuck. I have been following your guide step by step and everything has been moving pretty quickly. I'll give you a bit of background, 180l tank, medium planting, 10hrs lighting, dosed with liquid co2, 2 x airstones, 2 x filter/pumps, used filter medium from a friends tank. I think I'm on the verge of the first water change but not quite sure. Started the cycle last Saturday. Nitrites started showing pretty quickly, they have risen above what my jbl test set can show (above 1ppm) Nitrates raised to approx 200ppm as per jbl test set. This is not off the scale but very close to, has sat at this level for two days. My question is are the plants using the nitrates up therefore the levels aren't rising any further, would I be wise to do my 50% water ghange now or wait a bit longer? Any help you could give a complete noob would be most appreciated. Many Thanks.