Flowrate ...high or low?

Originally Posted by winq

hi guys, need some help here..

im intending to set up a 422 fgt with a 2ft OHF.. may i know wat is the

flowrate recommended? btw, my water level will be 40-50% only in the fgt.

sorry man.. after doin some hw.. i decided to use a fgt filter.. now i know to know wat is the recommanded flowrate for it? thanks alot..

cheem........

[itchy]

Currently have a 400l tank, looking to change the sump pump. Read through the threads n know that 4x is the recommend flow rate . Need advise, I'd I use 6x flow rate is it ok? Keeping some high bio load, 17inch aro with 2 small rays.

[arocomm]

My 6 x2.5x 2.5 with 4 feet sump tank. Current is running 2 eheim 1264. Is the flow rate too strong with my setup.

[angelo]

Flowrate is quantity over time, and speed/velocity is distance over time. Increase in flowrate will result in increase in speed only if cross-section of area remain constant. To reduce the speed with constant flowrate, just need to increase the cross-section area.

Our goal is to have high flowrate and low relative velocity between water and filter media. We just need to increase the cross-sectional flow area.

am i right that if i have slow flow rate for my tank. water take a longer time to travel around and reach the outlet. therefore More water can cover the areas of the medias MORE BB can be store at those medias?

Bro Atom thanks for the informations very useful.
Can please explain more about DO Vs pH Vs BBS?
DO affects the pH
pH affects both BBS and Fish
Just cannot figure out how to balance it.

Reduce the DO by cleaning your filter wool regularly, in that way the waste (poo) do not get easily dissolved into the tank and pollute the tank water.

Ensuring ph stability is necessary for all tanks. Ph naturally falls as a result of nitrification, buffering using sodium bicarbonate can be a solution, but monitoring the ph is essential to ensure it does not crash.

Quote:
Originally Posted by winq
hi guys, need some help here..

im intending to set up a 422 fgt with a 2ft OHF.. may i know wat is the

flowrate recommended? btw, my water level will be 40-50% only in the fgt.

sorry man.. after doin some hw.. i decided to use a fgt filter.. now i know to know wat is the recommanded flowrate for it? thanks alot..

You can use the calculator to determine the space. Thereafter, multiply it by the number of times of tank turnover. This will vary from 4 to 8, depending on bioload, feeding regime, pump used (headloss)etc.
You might want to settle for 6 times.

Currently have a 400l tank, looking to change the sump pump. Read through the threads n know that 4x is the recommend flow rate . Need advise, I'd I use 6x flow rate is it ok? Keeping some high bio load, 17inch aro with 2 small rays.

6 is fine.
Ensure that there is adequate filter media and the media is spread out evenly in the sump so that water flows into the media rather than around it. Get a good pump.

My 6 x2.5x 2.5 with 4 feet sump tank. Current is running 2 eheim 1264. Is the flow rate too strong with my setup.]

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!