when doing water changes...do you add prime or any kind of water conditioner? If not, you're killing BB and that's why you're not cycled. when you say your filters are clean....do you take it out and clean it in ever water change? if you do, that's also having the chance of killing off your cycle.... i wouldn't touch the filters till it's fully cycled. what are you using to test your water? water test kit or the dip sticks? if it's dip sticks .. throw them out and get an API water test kit...sorry for all the questions...but its needed to be answered