Hi Fishlore people, I need your guidance switching to sand from gravel. It's a 29, very established, with 5 harlequin raspboras, lots of Java fern and anubias and a little bacopa floating. Parameters are usually 0/0/10. Sometimes lately ammonia is 0.25. I add Prime if I see a little ammonia. Marineland Penguin 330 filter. Honestly I have neglected water changes and gravel vacuuming this past year, but parameters were always good (ammonia and nitrite were always 0, nitrates were climbing towards 80). This past month I have done much better with water changes weekly and have vacuumed most of the gravel, doing part of the tank each time. I would say 1/4 of the gravel has still not been vacuumed. I am trying to not go overboard vacuuming too much at once. Fish all look good. I need your advice about switching to sand. I don't want to mess up my cycle too much. Thankfully the tank is lightly stocked and the fish are hardy. Should I just go for it at this point, switch to sand, watch water parameters carefully? I have 5 panda cories in QT , they have been there almost 2 weeks. I'm definitely not wanting to move them until the 29 has sand. I think the cories will be fine in QT until this tank is ready. I welcome your advice!! I hope this post makes sense. I have never noticed ammonia in the 29 until very recently. Maybe because it's lightly stocked, low bioload fish, and I've been working on cleaning up the gravel.