Filter flow rate

[Rob Wilkinson]

This follows a thread I have about algae:

I have a Oase thermosmart 100 filter for an ADA 60-P
The filter is rated for 600LPH

I measured the flow following an algae outbreak and it was approx. 140LPH

I've just removed all filter media, cleaned down the inside, the propeller, and measured the flow again with no filter media in and it measured about the same.

This suggests that something else is restricting my flow (inline CO2?) or the filter is faulty. Before I take apart the whole set-up does anyone have any similar experience on this?

Thanks

 

[ceg4048]

Hello,
Filter flow ratings issued by vendors are always tongue in cheek. They are almost always measured at zero head and without media. Every foot of height below the water surface decreases the flow rate even more. Normally, the actual flow rate is somewhere between 40%-50% of the rating. This is exactly why we developed the 10X rule, so that we could compensate for these absurd marketing ploys.

In the real world the plants only need about 3X -5X turnover per hour, however, we are not living in the real world. We are living in a neural interactive simulation we call "The Matrix".

You should also be aware that apart from kinked hoses, any restriction in the circuit that reduces the effective cross sectional area of the tubing reduces the flow rate substantially. So for example, if the inside diameter of filter output spud is 16mm and you then place an in-line heater with it's spud having a 12mm inside diameter you will have reduced the flow rate by another 40%.

This unfortunate state of affairs often forces us to contemplate...just exactly what is "real"?


Cheers,

 

[Keith GH]

Hello Rob.

This older post might help you as well
https://www.ukaps.org/forum/threads/ada-60p-one-or-two-filter.43149/

I am referring to much of the information I have read and replied to being an Advisor. Moderator and Administer totalling close to 20 years with Aquarium Forums.

Your question is certainly not a new one. Filter rating is one big "Depends on" first being the makers ratings, it can be rather high and you wonder why your filter is a lot lower.

Here are some reasons.
Filter material packed too tight or dirty also the wrong filter materials.
Impeller filthy.
Hoses filthy also too small or too long.
Filter not in the best of location distance from outlet or too low.
Small hose connections.
Where the flow rate is measured from, at filter outlet or from the outlet in the tank.

Get every thing perfect and you are possibly close to the makers figures.

Keith