View Single Post
Old 05-01-2011, 01:47 PM   #71
Posts: n/a

Originally Posted by Spakase View Post
Tank has 850 litres. Flow rate (total) is 9,000 litres per hour?

Turnover = 10.6 times

The disadvantage of having too high a flow rate is that the contact time with the media is lowered, secondly, poo gets dissolved into the tank water faster (I think that was Atom's argument). Nevertheless, the gains outweigh the negative aspects because you get faster return of the tank water into the sump. This kind of flow rate would be good for super high bioload and high feeding schedules as ammonia spikes peak at feeding. But you do need to ensure that the sump has good filter media that allows a lot more nitrifying bacteria to build up.
If you keep few fishes and feed them sparingly, 10 time TO is way too high! It's just a matter of electricity cost, is it necessary to spend with no additional benefit. If you are okay with the cost, then it's not really an issue!
If the height of the setup is 5-6' , the head loss could be as much as 50%, meaning that the actual flow rate could be only 4-5000 litres per hour only instead of the projected 9000 litres per hour.

In that case, single pump users all have to upgrade bo??