Redragon, for filtration I am using a Fluval 404, a XP3 and a quick filter attachment on my powerhead. It keeps my water quality ok so it must be enough. Gravel vacs not to bad at all, I do it once a week draining about 20% of the water at the same time and I do hope my Piraya grow into monsters !!
I have 4 Caribe coming soon, not sure if I should try it overcrowded or lose some of the Reds.