Hay all well I have had my fish tank for about 2 years and I have never Changed the sand I only ask because I see green and win I do a deep water change "move rocks scrub walls scrap down and change water " I do this like once a month I do water change once a week and I rub glass every day so my question is I have never touched my sand bed ever and I see stuff growing in there win should I change and how do I do it all or part ?
