So my 13.5 Evo was 5 months old but then I took out the rock, bleached, and re started it. The sand bed, mechanical filtration sponge, bio filter, and carbon filter were all left untouched. I just tested the water and the nitrogen cycle is still working in my tank. I was just wondering if anyone would be able to give any input on how mature my tank would technically be by now after the rock restart.