Gravel planted tank - add sand or gravel or replace all?
I have a 48gal that has a good eco system going. I don't use charcoal or anything b/c the plants and fish keep things stable. We do a partial water change to vacuum the gravel every 6-8 weeks.
We have been considering moving to sand (read here it is better than gravel) but it is an established tank that is thriving (breeding bristle nose plecos and platty) and we have some rooted plants. We have about 1.5 inch of gravel so should we:
1) leave it alone b/c what we have is working
2) add a bit more gravel
3) add sand (Flourote or Eco Complete) on top of gravel
4) remove gravel and add sand (Flourote or Eco Complete)
TIA for advice!