flow rates for dummies

[jenga]

greetings peeps

please clarify the 10x rule for me and all other worm brains.

does it mean that the water in the tank has to be moved at a rate equivilent to 10x its volume to achieve this aim?
so a 100ltr tank would need to have a flow rate of 1000ltr per hour? where as the volume of water sent to a filter/s is an entirely different thing.

therefore you could use unfiltered powerheads to achieve the flow rate, without necessary filtering each and every drop.
Am i correct in this or should I return my ebay brain.

My new tank, arriving shortly, is 330ltr, and has a trickle fliter serviced by a 900ltr powerhead, which will not give me 900ltr per hour flow as the water is passed through a spray bar, so for all intents I my as well ignore this from my flow rate calculations.Correct???

great site btw...regards roy

 

[George Farmer]

Hi Roy and welcome to UKAPS!

Good question!

The 10x guideline assumes you have a regular external filter that do not produce their max flow rate.

So you have a 120 litre tank and filter it with a 1200lph external filter. In reality you're only get around 600lph perhaps. So in reality your getting 5x.

Powerheads produce much nearer their claimed flow rate, so you can take this into account when working out what filter/powerhead combo you require.

It's not an exact science, of course. Trial and error is often the only way to determine the best circulation rates and patterns for your individual set up.

There's so many other factors at work too.

How much decor and planting is there 'blocking' circulation? A typical Iwagumi layout will require less circulation output than a dense jungle, for instance.

What type of filter outlet do you have? A lily pipe has a different circulation pattern than a spray bar.

The size of the aquarium is a big factor too, of course. High energy large aquariums are much much tougher to achieve decent circulation.

All these factors combine to make the 10x rule nothing more than a rough, but good starting point guide.

 

[jenga]

thanks george for speedy response, I dont have any type of outlet yet, am here researching and saving money by using your brains instead of wifes purse. aquatics are a bit like fishing, more people get caught by the wonderful new tackle than fish, so i will continue pick you good peeps gray matter and enjoy learning