Thinking about a new skimmer

[Anonymous]

Well sort of.
My tank has been doing great, so I am relecutant to change anything. But I have been thinking about adding a fuge to my setup. However, I don't want to increase the power consumption of my tank at all (and would ultimately like to reduce it as much as possible). So, I was thinking that if I replaced my big becket skimmer with a more efficient needle-wheel I could probably plumb in a fuge and still end up with a net reduction in my electricity consumption.

I really, really love my skimmer, but it uses soooo much electricity.

So, what would be a good option?

First, I should say that, comparatively, I feed extremely heavy and I skim really heavily, so it will need to be a workhouse. Second, I'm not going to drop 4 figures on a skimmer.

My current skimmer is a big Barr Aquatic beckett which is really well built and would probably last for the rest of my life. But its currently fed with a Mag 24 pump using on the order of 265 watts!!!!!

Any thoughts?

 

[LA-Lawman]

how big is your tank again?

 

[Anonymous]

Its a 120 w/ about 60 more gallons in the sump.
It has a pretty heavy fish load.

 

[Anonymous]

I think the trick will be to balance the flow through the sump with the rate of skimming. If you can do that, any skimmer should work. The way some people are going about it is to us a recirculating skimmer fed by the overflow drains.

 

[Anonymous]

I think the trick will be to balance the flow through the sump with the rate of skimming. If you can do that, any skimmer should work. The way some people are going about it is to us a recirculating skimmer fed by the overflow drains.

huh?

 

[Anonymous]

Well sort of.
My tank has been doing great, so I am relecutant to change anything. But I have been thinking about adding a fuge to my setup. However, I don't want to increase the power consumption of my tank at all (and would ultimately like to reduce it as much as possible). So, I was thinking that if I replaced my big becket skimmer with a more efficient needle-wheel I could probably plumb in a fuge and still end up with a net reduction in my electricity consumption.

I really, really love my skimmer, but it uses soooo much electricity.

So, what would be a good option?

First, I should say that, comparatively, I feed extremely heavy and I skim really heavily, so it will need to be a workhouse. Second, I'm not going to drop 4 figures on a skimmer.

My current skimmer is a big Barr Aquatic beckett which is really well built and would probably last for the rest of my life. But its currently fed with a Mag 24 pump using on the order of 265 watts!!!!!

Any thoughts?

have you shopped for a more efficient pump?

 

[Anonymous]

I think the trick will be to balance the flow through the sump with the rate of skimming. If you can do that, any skimmer should work. The way some people are going about it is to us a recirculating skimmer fed by the overflow drains.

huh?

If your skimmer processes 800 gallons an hour, but you are running 1500 gallons through your sump, you are only skimming about 1/2 the water every cycle and you never really skim all the water in the system. If however, your return pump runs 800 gallons or less through the sump you are skimming all the water. It works even better if you have a chamber in the sump for the skimmer.
Some skimmers, recirculating skimmers, use the line from the overflow drain as the feed for the skimmer, while the pump with the needle wheel, or similar device, pulls water from inside the skimmer body instead of from outside the skimmer body in 'traditional' skimmers. This way all the water coming from the tank is skimmed.
This works very well with tanks designed to keep detritus in suspension as it allows the corals to feed, but skims out all the food without letting it settle.

 

[Anonymous]

I think the trick will be to balance the flow through the sump with the rate of skimming. If you can do that, any skimmer should work. The way some people are going about it is to us a recirculating skimmer fed by the overflow drains.

huh?

If your skimmer processes 800 gallons an hour, but you are running 1500 gallons through your sump, you are only skimming about 1/2 the water every cycle and you never really skim all the water in the system. If however, your return pump runs 800 gallons or less through the sump you are skimming all the water. It works even better if you have a chamber in the sump for the skimmer.
Some skimmers, recirculating skimmers, use the line from the overflow drain as the feed for the skimmer, while the pump with the needle wheel, or similar device, pulls water from inside the skimmer body instead of from outside the skimmer body in 'traditional' skimmers. This way all the water coming from the tank is skimmed.
This works very well with tanks designed to keep detritus in suspension as it allows the corals to feed, but skims out all the food without letting it settle.

okay, i just had delete a whole line of thought here when i realized that PitPat, running a beckett, could be running all his water through his skimmer or maybe he is considering that, or maybe that is what you are advising.

i thought you were saying that a traditional type skimmer (like an early needlewheel) placed in sump would be better run with a return pump that matched the rated GPH of the skimmers needlewheel actual output.
if you happen to believe that... well then, i disagree.

 

[Anonymous]

Why would you disagree?

 

[Anonymous]

Why would you disagree?

in short, a skimmer would produce less protein when skimming from a cleaner source.
if the turnover is lessened, so is the soiled water that acts as supply to the skimmer.

 

[Anonymous]

Why would you disagree?

in short, a skimmer would produce less protein when skimming from a cleaner source.

If the water is cleaner because it has already been skimmed, thats good. When I feed and turn the return pump back on my skimmer goes nutty, but during the rest of the day it doesn't do that much because there isn't much for it to do.

if the turnover is lessened, so is the soiled water that acts as supply to the skimmer.

Only if the turnover is lessened to less than the skimmer can process.
If 1/2 the water involved in tank turnover doesn't get skimmed at all, then that water isn't supplying the skimmer at all. The 'extra' water goes right by the skimmer and back into the tank which also gives you diminishing returns on the ickies in that water making it to the skimmer, just like with smaller water changes.

 

[Anonymous]

Why would you disagree?

in short, a skimmer would produce less protein when skimming from a cleaner source.

If the water is cleaner because it has already been skimmed, thats good. When I feed and turn the return pump back on my skimmer goes nutty, but during the rest of the day it doesn't do that much because there isn't much for it to do.

the blue is what i want to respond to... it isn't good if there is plenty of water left unskimmed elsewhere in the system.
the bottom line for me is skimmate removed. the longer it takes to remove it the less desirable the system.
maybe other peoples tanks get too clean but i have never, at least to my knowledge, had a problem with a lack of funk in the water.
any sump that skims less than 100% of the water at it's inlet will ever reach 100% without recirculating cleaned water many times over. i don't believe that is good in terms of efficiency, be it energy use or otherwise

if the turnover is lessened, so is the soiled water that acts as supply to the skimmer.

Only if the turnover is lessened to less than the skimmer can process.
If 1/2 the water involved in tank turnover doesn't get skimmed at all, then that water isn't supplying the skimmer at all. The 'extra' water goes right by the skimmer and back into the tank which also gives you diminishing returns on the ickies in that water making it to the skimmer, just like with smaller water changes.

any amount of lessening is less.
that seems like an irritating moron response but there is truth to it.
being a cycle, anything short of that 100% is less. the best that can be done is to make the sump water parameters as close to 100% as possible.
i don't see how there can be diminished returns as you describe them in a closed system like this.
the increased circulation that causes the water to pass by the skimmer as you described in a given sump also causes the water to circulate out of the main tank before it has time to pick up as much funk.
thus the main tank has cleaner water.
i don't mean to say that there need be a massive overturn of water from top to bottom, but there will be a loss of skimmer efficiency directly related to GPH.
how much of a loss is beyond my ability to calculate.

to me, the bottom line is funk removed.
if you can convince me that lessening the cycle volume equates to a larger protein production i would have to agree with you... and i would appreciate such a convincing as well.

 

[bleedingthought]

Marcus, get a recirculating skimmer. Ben will probably tell you the same!

 

[LA-Lawman]

i would say yes.... recirc. get the biggest you can afford. THe H&S and deltec/DAS skimmers are great....

needlewheel is the way to go....

 

[Anonymous]

Why would you disagree?

in short, a skimmer would produce less protein when skimming from a cleaner source.

If the water is cleaner because it has already been skimmed, thats good. When I feed and turn the return pump back on my skimmer goes nutty, but during the rest of the day it doesn't do that much because there isn't much for it to do.

the blue is what i want to respond to... it isn't good if there is plenty of water left unskimmed elsewhere in the system.

There is always new waste in the system. The question is where and when it goes through the skimmer.

the bottom line for me is skimmate removed. the longer it takes to remove it the less desirable the system.

I agree. The limiting factor is the amount of water your skimmer can skim. If your skimmer is in the sump and your return pump moves more water through the sump than the skimmer can skim it will take longer to skim all the water in the system.

any sump that skims less than 100% of the water at it's inlet will ever reach 100% without recirculating cleaned water many times over. i don't believe that is good in terms of efficiency, be it energy use or otherwise

If your sump moves more water than the skimmer can skim you are pushing unskimmed water back into your tank, but I don't think I am really following what you are saying above.

if the turnover is lessened, so is the soiled water that acts as supply to the skimmer.

Only if the turnover is lessened to less than the skimmer can process.
If 1/2 the water involved in tank turnover doesn't get skimmed at all, then that water isn't supplying the skimmer at all. The 'extra' water goes right by the skimmer and back into the tank which also gives you diminishing returns on the ickies in that water making it to the skimmer, just like with smaller water changes.

any amount of lessening is less.

Only if you lessen it to less than the skimmer can process.

that seems like an irritating moron response but there is truth to it.
being a cycle, anything short of that 100% is less. the best that can be done is to make the sump water parameters as close to 100% as possible.

Not sure what that means.

i don't see how there can be diminished returns as you describe them in a closed system like this.

Its about dilution. http://www.advancedaquarist.com/issues/ ... /short.htm

the increased circulation that causes the water to pass by the skimmer as you described in a given sump also causes the water to circulate out of the main tank before it has time to pick up as much funk.
thus the main tank has cleaner water. i don't mean to say that there need be a massive overturn of water from top to bottom, but there will be a loss of skimmer efficiency directly related to GPH.
how much of a loss is beyond my ability to calculate.

Sorry, I thought I mentioned the need to not rely on your return pump for in tank circulation.

to me, the bottom line is funk removed.
if you can convince me that lessening the cycle volume equates to a larger protein production i would have to agree with you... and i would appreciate such a convincing as well. [/b]

[/quote]

Its more efficiently running the water to the skimmer. Check out the dilution article and think of the skimmer as the water change.

 

[Anonymous]

Thales,

i don't know if we are on the same page at all.

i am aware of the dilution effects of water change percentages.. although i am certainly not an expert on the subject.
it only cuts the mustard to a point here... we aren't actually changing any water out and because it is a closed system the water we are cleansing is coming back to the skimming process again, regardless.
how clean that returning water is depends upon how much of it has recently been run through a skimmer.

you can consider the entire process and divide it into cycles, as i believe we both have been discussing. a cycle would be nothing more than an undertermined length of time.
during this time a specific volume of water will be available to the skimming process and that volume available will depend directly upon our return pumps actual output.
ideally we would want the volume of raw water processed by the skimmer (different from the actual amount available to the skimming process) to be equal to the skimmers maximum output.
realistically this can only be obtained by running the entire volume of water single file through the skimmer. this is not what oyu and i have referred to as traditional.


let's say a skimmer has an output of 2000 GPH and a 1 hr cycle subjects 2000 gallons to the skimming process via a 2000 GPH return pump.
this will run more water through the skimmer twice than it would if the volume subjected was increased to 3000 gallons using a larger return pump.
now, i believe the funkier the skimmer's inlet water, the more funk a skimmer will remove, agreed?
so running more through the skimmer twice means the total gallonage skimmed was cleaner so you will remove less funk using the 2000 GPH return pump.

i would like to C&P one thing you said earlier as i think it is important in understanding each other..

the bottom line for me is skimmate removed. the longer it takes to remove it the less desirable the system.

I agree. The limiting factor is the amount of water your skimmer can skim. If your skimmer is in the sump and your return pump moves more water through the sump than the skimmer can skim it will take longer to skim all the water in the system.

i find this faulty.

while one return pump might be transfering 98% skimmed water it might only be doing it at 1000 GPH whereas a more efficient design could be moving return water that is 50% skimmed at 3000 GPH.
the second one will skim the entire volume quicker... no?
BTW, these are hat drawn numbers and not meant to be anything close to actual.

i think a more accurate limiting factor would be the amount of raw water your skimmer has access to, the more raw water that you throw by it the more it can skim.
of course this isn't the only limiting factor.
the work a given skimmer can perform is definately worth considering.

anyway, i wouldn't be at all surprised if i am missing something larger in the picture here.

my apologies to PitPat as i am not really discussing his skimmer anymore.

 

[Anonymous]

have you shopped for a more efficient pump?

I've looked a little.
I haven't found any pumps that use significantly less power than the Mag 24 but that can still match its output. I could probably get away with a less powerful pressure-rated pump, but I think my electricity savings would still be slight compared to using a recirculating skimmer that is fed from my return pump.

 

[Anonymous]

I don't have 2400 gallons of water/hour turnover through my sump, so some of the power used to drive the skimmer is probably wasted.

 

[Anonymous]

i would say yes.... recirc. get the biggest you can afford. THe H&S and deltec/DAS skimmers are great....

needlewheel is the way to go....

That is what I suspected.
But if I do the math, it would take a really long time to save as much money in electricity as I would spend on a skimmer upgrade. The plus side of the Beckett skimmers is, that aside from the pump, they are comparatively very affordable to buy.

 

[Anonymous]

Thales,

i don't know if we are on the same page at all.

i am aware of the dilution effects of water change percentages.. although i am certainly not an expert on the subject.
it only cuts the mustard to a point here... we aren't actually changing any water out and because it is a closed system the water we are cleansing is coming back to the skimming process again, regardless.
how clean that returning water is depends upon how much of it has recently been run through a skimmer.

Think of dilution as a principle. Instead of changing water we are skimming water. If half (or whatever) the water going by the skimmer in the sump is not skimmed, and that 'dirty' water is mixed with skimmed water the dilution idea comes into play and it takes longer for that unskimmed water to get back to the skimmer. Even when it does get back to the sump, there is a chance it will go right by the skimmer again unskimmed.

ideally we would want the volume of raw water processed by the skimmer (different from the actual amount available to the skimming process) to be equal to the skimmers maximum output.

Wait a sec, this is my whole point.

realistically this can only be obtained by running the entire volume of water single file through the skimmer. this is not what oyu and i have referred to as traditional.

I don't know about traditional or not, but there are lots of people doing just that for a while now. Some via recirculating skimmers, some with a skimmer chamber where water must be skimmed before it moves on through the sump and gets moved on through the sump via the skimmer exit pipe.

let's say a skimmer has an output of 2000 GPH and a 1 hr cycle subjects 2000 gallons to the skimming process via a 2000 GPH return pump.
this will run more water through the skimmer twice than it would if the volume subjected was increased to 3000 gallons using a larger return pump.

I don't understand the second sentence.

now, i believe the funkier the skimmer's inlet water, the more funk a skimmer will remove, agreed?

Sure, but the point is to remove the funk, not leave it around so the skimmer skims evenly 24 hours a day.

so running more through the skimmer twice means the total gallonage skimmed was cleaner so you will remove less funk using the 2000 GPH return pump.

But ti doesn't all go through the skimmer - that depends on how much your skimmer skims per hour, not how much water goes through the sump. You aren't running more through the skimmer twice, you are running the same through the skimmer and moving the same right by the skimmer unskimmed.

I agree. The limiting factor is the amount of water your skimmer can skim. If your skimmer is in the sump and your return pump moves more water through the sump than the skimmer can skim it will take longer to skim all the water in the system.

i find this faulty.

while one return pump might be transfering 98% skimmed water it might only be doing it at 1000 GPH whereas a more efficient design could be moving return water that is 50% skimmed at 3000 GPH.
the second one will skim the entire volume quicker... no?

Depends on how much the skimmer can process. Return little to do with how much water the skimmer skims. If your skimmer does 500 gph, 1000 gph through the sump mean 50% of the water through the sump isn't touched by the skimmer.

i think a more accurate limiting factor would be the amount of raw water your skimmer has access to, the more raw water that you throw by it the more it can skim.
of course this isn't the only limiting factor.
the work a given skimmer can perform is definately worth considering.

Your skimmer can only skim as much as it can skim regardless of how much water is moving by it. If you though more water by it than it can skim, the water that it does skim is diluted by dirty water.

anyway, i wouldn't be at all surprised if i am missing something larger in the picture here.

my apologies to PitPat as i am not really discussing his skimmer anymore.