Hi everyone! Just joined and really don't know my way around. Got a "welcome" and can't figure out how to thank them! I just finished a fishless cycling of a 10 gallon tank with live plants and fine sand, a heater with no up or down switch, a Nano10 zoo med filter with the tubes. MY nitrates are 20ppm and I read thay should be between 5 and 10ppm to be safe for fish. I've changed 95% of the water and removed dead leaves but still at 20ppm! My question is can I clean the filter tubes with are full of dirt and rinse the sponge and ceramic media in aquarium water or change the water again or what to bring the nitrates levels down? I'm to be picking up fish i ordered tomorrow afternoon so don't have much time to get it right! I'm stocking my tank with 5 pgym corys and 1 betta male. Only putting in the corys tomorrow and will get betta end of week. What to do?