Well the water filter rated at 1 liter/min at water pressure 12 psi. Water pressure applicable is 12-45psi. Since my tap water pressure quite high, took less than 1 hour to do 40-50% water change weekly. Of course, I clean the ceramic filter cartrigde before that. See more FAQ about this water filter. By the way this water filter is using only 3 filter cartridges not like other model which using 6 filter cartridges. I could imagine how slow that water filter model. I do not have the exprience using an RO unit, but it will be a lot slower, I think, since using some kind of membrane.

I know the product is not 100% perfect, but what other alternatives I have. Either that or keep losing fish. Also using this filter is useless, IME, which by the way "berlambak" at your nearest Carrefour.

I don't know about that, but you can see this under "Make your fish feel at home". Does not looks like marine fish to me.

Best Regards