TMC Reef Pump flow rates

Kaaaarrrll · Jan 15, 2021

I posted the same question in my build thread but thought it may get some more views and an answer here.

Quick question i was wondering if anyone knew the answer to the following. What is the minimum flow rate if the TMC Reef Pump 8000, there isn’t much if any information I can find except that it’s max flow rate is 8000lph. I did find a few posts suggesting that it is 2000lph but nothing concrete.
TIA

MnFish1 · Jan 15, 2021

The max is 8000 liters/hour (as you said) - if you look on their website - there is a chart showing the flow with varying heights of 'head' (i.e. how far up the pump as to pump) - https://www.completeaquatics.co.uk/catalog/product/view/id/12469/s/tmc-reef-pump-8000-dc/

For example at 5 meters head - the flow is 'zero' at 2 meters the flow is about 5500 L/H (on the chart it says 5.5 T/hour - not sure what that means) - but in any case the chart is there.

Kaaaarrrll · Jan 15, 2021

Thanks for the link and reply it’s much appreciated, I had seen that chart but I think it’s for flow rate at max power depending on head height. The pump has a controller with 20 stages. With 20 being max power and 1 being low power.

What I would like to know is how much water is being pumped on the lowest setting at 0 head height. I can run a test and work it out but was hoping someone maybe already had

MnFish1 · Jan 15, 2021

Kaaaarrrll said:
Thanks for the link and reply it’s much appreciated, I had seen that chart but I think it’s for flow rate at max power depending on head height. The pump has a controller with 20 stages. With 20 being max power and 1 being low power.

What I would like to know is how much water is being pumped on the lowest setting at 0 head height. I can run a test and work it out but was hoping someone maybe already had

I would assume - that you could 1. Call the company (because without knowing the settings at each level - it would be impossible to determine each 'level) or 2. Extrapolate using their chart - for example - we know that at 0 head - the pump is pumping 0. it could very well be that those settings are 1/20 so lets say at the lowest setting (1) - I would assume that its 1/20 of max (i.e. 8000/20=400 liters/hr), setting (2) would be 800, etc etc - up to setting 20 (the highest) - which is 8000. But - I'm not sure - its my assumption - again at 0 head my guess is that at higher head height these calculations might not be 'correct' - but would require measurement or confirmation from the company. I'm curious - why do you want a pump that is pumping at variable speeds? - I mean if you're going to use it at setting 10 (assume thats 4000 l/hr) - why not just get a 4000 pump instead of the 8000?

Kaaaarrrll · Jan 15, 2021

MnFish1 said:
I would assume - that you could 1. Call the company (because without knowing the settings at each level - it would be impossible to determine each 'level) or 2. Extrapolate using their chart - for example - we know that at 0 head - the pump is pumping 0. it could very well be that those settings are 1/20 so lets say at the lowest setting (1) - I would assume that its 1/20 of max (i.e. 8000/20=400 liters/hr), setting (2) would be 800, etc etc - up to setting 20 (the highest) - which is 8000. But - I'm not sure - its my assumption - again at 0 head my guess is that at higher head height these calculations might not be 'correct' - but would require measurement or confirmation from the company. I'm curious - why do you want a pump that is pumping at variable speeds? - I mean if you're going to use it at setting 10 (assume thats 4000 l/hr) - why not just get a 4000 pump instead of the 8000?

Thanks for the reply,

Like yourself, i had initially assumed that at setting 1, it would be 1/20th of max flow and so on. However i discovered a few posts suggesting that setting 1 is circa 2000lph but i couldn't find any specs that confirmed my assumption or 2000lph.

I guess I'm going to have to test it as i'm just trying to work out what the ideal setting is going to be for my tank. I have a display volume of circa 250 litres which I'm looking to cycle through the sump on the slower side of things. So if the min flow rate is 2000lph then setting 1 or 2 will be ample or if 1 setting is 1/20th of max flow then i will need to work it out.

Few reasons why i'm using a variable pump with such a high max flow rate, firstly its much quieter running a pump on low settings than on high settings, secondly its effectively working less to do the same job that a smaller pump would need to work at, thus increasing its life span. Thirdly it allows for tank size upgrade without the need to buy a new pump and fourthly it wasn't that much more expensive than the 4000 model...

MnFish1 · Jan 15, 2021

Kaaaarrrll said:
Thanks for the reply,

Like yourself, i had initially assumed that at setting 1, it would be 1/20th of max flow and so on. However i discovered a few posts suggesting that setting 1 is circa 2000lph but i couldn't find any specs that confirmed my assumption or 2000lph.

I guess I'm going to have to test it as i'm just trying to work out what the ideal setting is going to be for my tank. I have a display volume of circa 250 litres which I'm looking to cycle through the sump on the slower side of things. So if the min flow rate is 2000lph then setting 1 or 2 will be ample or if 1 setting is 1/20th of max flow then i will need to work it out.

Few reasons why i'm using a variable pump with such a high max flow rate, firstly its much quieter running a pump on low settings than on high settings, secondly its effectively working less to do the same job that a smaller pump would need to work at, thus increasing its life span. Thirdly it allows for tank size upgrade without the need to buy a new pump and fourthly it wasn't that much more expensive than the 4000 model...

Yes I noticed that about the price.