i have a Juwel Rio 400, and i have the internal filter that comes as standard with this tank, plus 2 external filters, in total i think i have around 3500 L/H on my tank and my water is crystal clear !
Yeah I have a Fluval Roma 200, using an AquaManta EFX external filter along with a small internal that does about 300-400 L/hr.. gives the tank something like 1400 L/hr total and makes a nice current around the tank with no stagnant spots Water's probably pretty similar to Benakaben's ;D