Skimmer pump question - general

[DarG]

This is a general question regarding pump sizing for skimmers.
My skimmer is a Bermuda Aquatics 3C but would also apply to my Reef Devil and should apply to any skimmer that uses a single drive pump (not NW or the like).

Is there any advantage to a stronger pump if a smaller pump is more than enough?

Let me explain:

Assume you have a skimmer and you have two pumps to choose from, both pressure rated and both capable of running the skimmer.
Pump 1 is rated for 600 gph and a maximum head of 17 feet .
It is smaller than pump 2 but still needs to be throttled down a little bit in order to not overdrive the skimmer.

Pump 2 has a higher GPH rating, 800 gph, than pump 1 and is rated for a max head of 21 feet. Pump 2 needs to be throttled down further than pump 1 in order to not overdrive the skimmer.

Both pumps are clearly capable of running the skimmer in that both must be throttled down to different degress in order to not overdrive the skimmer. One has a lower GPH and lower max head.

So, is there any advantage to using the stronger pump with the higher max head rating (or the smaller pump with lower max head for that matter)? Again, both must be throttled down.

If one is better than the other, please explain why.

Thanks

 

[skwirl]

the lower gph one is better.. it uses less wattage.. it also may not be quite as turbulent going through, but the only real difference i can think of is wattage.

 

[DarG]

So the higher pressure rating of the larger pump doesnt come into play any in terms of better skimming?

 

[kodyboy]

higher pressure would be better for beckets/downdrafts, but for venturis I am not sure. I would think higher flow would equal (to an extent) more air pull, but there is probably a limit to the gains.

 

[DarG]

But if you are throttling down both pumps, one just more than the other, ultimately you are acheiving the same flow into the skimmer, right?

Its the effect, if any, that the higher pressure pump would have in that situation that I was wondering about. Unless I'm way of base.

Does pressure rating and/or flow have any bearing on how well the skimmer will skim if both the smaller and larger pumps both need to be throttled down, just by different amounts, to keep from overrunning the skimmer?

The common question is whether a pump is strong enough to power a skimmer. But if 2 pumps both need to be throttled down to keep from overdriving the skimmer then both pumps are obviously capable of running the skimmer. So I guess what I'm asking is if going with the higher GPH rated and pressure rated pump is any better when the lower rated one is already capable of overrunning the skimmer.

 

[DarG]

Bump...

More opinions, facts? Skimmer Experts?

 

[DarG]

Nobody else?

 

[DarG]

Somebody?