How much flow please?

[Tropical Tony]

Hi guys I’ve just set up a planted aquarium and want to tank the internal filter out for an external. My question is what flow should I be aiming for? The tank is 150 litres. Cheers. TT

 

[Colin_T]

The average turnover rate for a freshwater tank is 2-5 times the tank volume per hour, however it also depends on what fish you want to keep.

If you have Rift Lake cichlids or fishes keep in water with a high pH (above 7.5), have a higher turnover rate (5-10 times per hour) to make sure there is no ammonia in the water. Ammonia is more toxic in alkaline water (pH above 7.0).

If you have tetras and other soft water fishes that occur in slow moving water ways, have a lower turnover rate (2-3 times per hour).

 

[Tropical Tony]

thanks. I’m just keeping terras/community. So ideally a 450lph flow would be fine for my carpet plants and fish?

 

[Colin_T]

yeah it should be fine

 

[Byron]

In this sized tank and with the intended fish, I would have either a small internal filter like the Aqueon Quiet Flow or a dual sponge filter. I ran my 40g with the dual sponge for three years with small tetras, pencilfish and cories, and it was planted.