how many times a hour should the water go through the sump?

[Zoaelite]

Mr. Wilson,
First of all thank you for that properly constructed post if every single person on this forum was like you I don't think I would ever stop reading . I will break my "No more posting" post as there are finally some factual intelligent comments on here.

The only one major difference between what you have described and what takes places in the average reefer's sump is that almost in all cases the skimmer is never fed by the return. In the future I might design my sump like this as its an interesting concept and I'm sure it would save energy/ increase efficiency. Just out of curiosity do you have any photos of your sump as I would love to take a look?

Now that being said, as most sumps are not like this and include a sump volume with multiple apparatus drawing water out of that volume (and not being plumbed in line). We can determine that some of this water is leaked and gets pumped back into the main tank has to be dirty (as there is no way you could 100% clean this before it makes its way back).

So if dirty water is being plumbed into the tank anyways why not increase the flow so there is constantly a new supply of DOC and surfactants for the skimmer to skim off? Also with the advent of Biopellet reactors, Zeovit and other nitrate/ite/NH3 sinks would it not be more beneficial to have a higher turn over to supply fresh dissolved (As compared to surface) organics to these reactors?

[mr.wilson]

Originally Posted by zoaElite

Mr. Wilson,
First of all thank you for that properly constructed post if every single person on this forum was like you I don't think I would ever stop reading . I will break my "No more posting" post as there are finally some factual intelligent comments on here.

The only one major difference between what you have described and what takes places in the average reefer's sump is that almost in all cases the skimmer is never fed by the return. In the future I might design my sump like this as its an interesting concept and I'm sure it would save energy/ increase efficiency. Just out of curiosity do you have any photos of your sump as I would love to take a look?

Now that being said, as most sumps are not like this and include a sump volume with multiple apparatus drawing water out of that volume (and not being plumbed in line). We can determine that some of this water is leaked and gets pumped back into the main tank has to be dirty (as there is no way you could 100% clean this before it makes its way back).

So if dirty water is being plumbed into the tank anyways why not increase the flow so there is constantly a new supply of DOC and surfactants for the skimmer to skim off? Also with the advent of Biopellet reactors, Zeovit and other nitrate/ite/NH3 sinks would it not be more beneficial to have a higher turn over to supply fresh dissolved (As compared to surface) organics to these reactors?

Sorry, I guess I wasn't clear. The protein skimmer is not fed by the sump return pump directly. The water first passes through the display tank for an unknown amount of time. The water eventually overflows into the overflow box where it is then available to the skimmer. I wish there was a FIFO (first in first out) system that would assure display tank water is processed at maximum efficiency. For our purposes, we will call the display tank water "dirty" and the sump water "clean".

If you install a single glass partition wall to segregate your protein skimmer in a an area we will call the "skimmer zone", and you plumb the protein skimmer effluent so it puts the "clean" water into the second zone, then you will process 100% of the water entering the sump, providing your sump return pump is matched to the output of your skimmer pump.

Let's look at an example. If you have a tank between 75-300 gallons you will likely be using a modified laguna Max-Flo 1500 pump that produces 800-1000 LPH air, and 450-500 GPH of water throughput. This is the pump you will find on Royal Exclusive Bubbleking and ATB models. Protein skimmers using Sicce PSK-2500 pumps have approximately 660 GPH output, but that is dialed back as more air is introduced.

Now that we know 500 GPH is the maximum amount of water we can treat, we match our sump return pump accordingly. Simply go to a handy head loss calculator and punch in your head distance, pipe size, and plumbing parts. http://www.reefcentral.com/index.php...oss-calculator I picked Poseidon/Velocity PS2 for cost effectiveness, low heat transfer, external pump, and absolutely dead quiet operating sound. My calculation came up with 592 GPH, and 664 GPH with the PS3. The price and power consumption is the same for both models so I would go with the larger PS3 and run a bypass of 150 GPH through a UV sterilizer. If you are an energy miser go with an external powerhead of some sort. You should be able to move that much water using half as much electricity. Personally I feel it's cheaper to pay for the extra electricity with the comfort of knowing your PS2 or 3 will run for many years without service. Or take that $5.00 energy savings per month and keep it in a jar. You will be able to buy a new powerhead in three years when that one dies. They will be running on solar or wind by then anyway

There is no reason why media reactors or bags of media in a dam & weir can't be fed strictly "dirty" water. The water exits the skimmer and flows over the media bag once as it travels through the sump, or your media reactor effluent is directed to the third zone so it is only treated once.

[banditpowdercoat]

One way you get close to a FIFO style sump is with a recirc style skimmer. If the drain of the tank is fed Directly into skimmer, then the skimmer will skim 100% of the sump flow.(to the skimmers efficiency's of course) The Sump return pump would then only need to be sized for the skimmers need. But, it seem's most skimmers now are being made single pass.

[StirCrazy]

Originally Posted by banditpowdercoat

One way you get close to a FIFO style sump is with a recirc style skimmer. If the drain of the tank is fed Directly into skimmer, then the skimmer will skim 100% of the sump flow.(to the skimmers efficiency's of course) The Sump return pump would then only need to be sized for the skimmers need. But, it seem's most skimmers now are being made single pass.

recirc skimmer are usaly fed slow Dan, it would work but not sure if it would be any better.

Steve

[banditpowdercoat]

Originally Posted by StirCrazy

recirc skimmer are usaly fed slow Dan, it would work but not sure if it would be any better.

Steve

I know, hence the needing slow sump flow, or a REALLY large skimmer that would be so costly as to make the FIFO design not that appealing.


But really, in a sump with your skimmer, how much water is being recirced by a regular one pass skimmer in a sump chamber? Sure, you match sump flow to skimmer flow, but there is allways skimmer outlet water that will be sucked back into the inlet. Only true way to ensure that doesnt happen is to feed skimmer from different compartment.

[mr.wilson]

Originally Posted by banditpowdercoat

I know, hence the needing slow sump flow, or a REALLY large skimmer that would be so costly as to make the FIFO design not that appealing.


But really, in a sump with your skimmer, how much water is being recirced by a regular one pass skimmer in a sump chamber? Sure, you match sump flow to skimmer flow, but there is allways skimmer outlet water that will be sucked back into the inlet. Only true way to ensure that doesnt happen is to feed skimmer from different compartment.

As I stated in an earlier post, the Sicce PSK 2500 pump used on many skimmers has a maximum output of 660 GPH. I would suspect less than that with the high range of air to water ratio that pump offers. Another very popular skimmer pump is the Laguna Max-Flo which puts out 450 GPH in most cases. These are pumps that you will see on high end skimmers that are rated for tanks up to 300 gallons.

A magic number like 10 or 20 x the volume of the tank turnover has absolutely no bearing on the issue at hand when the protein skimmer used is the same for a 75 or 300 gallon tank. The display/sump throughput should be 500 GPH which is equal to 6.6666 x for the former and 1.6666 for the latter.

I would suggest you use a bucket and stopwatch to meter the exact output of the skimmer once it is broken in and running at maximum efficiency with respect to air intake/production. Only then will you have hard numbers of skimmer pump water flow rates.

Some of the large Beckett skimmers require a very strong feed pump, but these are typically plumbed right into the display tank with an influent at one end and the effluent at the other. They may be sitting in a sump or catch basin, but they are usually plumbed independent of them.

[mr.wilson]

Originally Posted by StirCrazy

recirc skimmer are usaly fed slow Dan, it would work but not sure if it would be any better.

Steve

As bandit pointed out, our goal here is to move water from the display tank to the sump and back for the purpose of filtration. If the filtration only requires a slow throughput, then that's all we need to give it.

If your recirculating skimmer needs 300 GPH throughput, it doesn't matter how big your tank is, you need to install a sump return pump that delivers 300 GPh to the display and subsequent sump/skimmer.

[Bloodasp]

Just like i said match your flow with your equipment.

[StirCrazy]

Ok this whole thing is bing made a lot more complacated that it has to be. let me try clarafy and put an end to the back and forth which is getting no where and just confusing people reading this.

Ok so I will put forth 2 senarios for you to read and tell me which one works better all equipment is the same so tank is 80 gal sump is 30 gal, skimmer is fed by a 500gph pump

so senario 1, lets match the skimmer so the return flow is 500 gal per hour

Senario 2, lets use a bigger return pump so the flow is 1500 gph.

and heck let throw one more in
senario 3 lets match the tank, flow rate is 30 gal per hour.

so in senarios 1+2 the skimmer is given all the water it can handle but yet in senario 3 you are starving the skimmer.

so lets pick a number and say that this skimmer is 20% efficient (picked 20 as it is easier to work with) which means in 1 hour this skimmer will reduce the "crap" in 500gal of water by 20%

so our total water volume in these systems is the same at 100gal

system 1 the skimmer has all the water it can handle so it reduces the waist to it theoretical maximum reduction. as per the article Mr Wilson poster that is about a 80% removal.

in system number 2, the exact same amount of water is processed, so you get the same results as system 1.

but in system 3 where we matched the tank size for a 1X turnover, the skimmer only sees 80gal in that hour, but since it skimms the hell out of that 80 gal it is reduced to the max pull down so 80% clean 20% dirty then mixed with the 100% dirty water in the display so 80 gal at 20% mixed with 20 gal at 100% is going to give you about a 35% dirty mixture as aposed to the 20% from the first 2. so you can see if we matched the sump flow for a 1X turn over it would be even worse as we would have 20 gal of 80% clean water mixing with 80 gal of 100% dirty, which would end up with a number of 84% dirty.

So what do we get from this, not enough flow is very bad, to much flow works good but isn't efficient in power used for moving the water.

heaters will work just as good in high flow as in low flow but they transfer more heat to a perticular sample of water in a lower flow, but in a closed system where we have constant cirulation the end result will be the same. and to low a flow can cause heat gradiants which you don't want. as for UV this is a hard one as you have to match the flow written on the UV unit.. mine wanter 400 to 550 gph so I gave it a 550gph pump and knew there would be between 50 and 100gph of losses, chiller same thing match the flow rating.

so the way I had my tank set up I created massive amounts of flow in the display to keep everythign suspended. my surface was very turbulant so I never developed bio film that needed to be skimmed off the surface. but I still used a smooth overflow to reduce noise and I had the water flowing over it at a depth of about 1/4" so I would have enough water flow to carry suspended junk to the sump.

from the sump I had one pump tt remove water for my skimmer, this sucked from my settling pond and returned at the return pump chamber, my heaters were located in the settleing pond where the flow was a little lower. I had two pumps pull water out of the return pump chamber and send it to the chiller and the UV then return at the very bigining again to help keep the flow in the bigining section very fast and turbulant so any suspended matter wouldn't fall out befor the settling pond.

the result of this system was very very little cleaning of crap from the bottom of the desplay, but lots from the settling pond which is what I wanted. I would shut down the return pump, skimmer pump and UV pump, suck all the water from the settling area (about 20) then put my new salt water in there and water change and clean up was done. I don't like refuge, algae or anything else in the sump, as they do need a low flow, so I had my refuge remote and I pumped water to it and it trickeled back into the display directly.

Steve

[mr.wilson]

Originally Posted by StirCrazy

Ok this whole thing is bing made a lot more complacated that it has to be. let me try clarafy and put an end to the back and forth which is getting no where and just confusing people reading this.

Ok so I will put forth 2 senarios for you to read and tell me which one works better all equipment is the same so tank is 80 gal sump is 30 gal, skimmer is fed by a 500gph pump

so senario 1, lets match the skimmer so the return flow is 500 gal per hour

Senario 2, lets use a bigger return pump so the flow is 1500 gph.

and heck let throw one more in
senario 3 lets match the tank, flow rate is 30 gal per hour.

so in senarios 1+2 the skimmer is given all the water it can handle but yet in senario 3 you are starving the skimmer.

so lets pick a number and say that this skimmer is 20% efficient (picked 20 as it is easier to work with) which means in 1 hour this skimmer will reduce the "crap" in 500gal of water by 20%

so our total water volume in these systems is the same at 100gal

system 1 the skimmer has all the water it can handle so it reduces the waist to it theoretical maximum reduction. as per the article Mr Wilson poster that is about a 80% removal.

in system number 2, the exact same amount of water is processed, so you get the same results as system 1.

but in system 3 where we matched the tank size for a 1X turnover, the skimmer only sees 80gal in that hour, but since it skimms the hell out of that 80 gal it is reduced to the max pull down so 80% clean 20% dirty then mixed with the 100% dirty water in the display so 80 gal at 20% mixed with 20 gal at 100% is going to give you about a 35% dirty mixture as aposed to the 20% from the first 2. so you can see if we matched the sump flow for a 1X turn over it would be even worse as we would have 20 gal of 80% clean water mixing with 80 gal of 100% dirty, which would end up with a number of 84% dirty.

So what do we get from this, not enough flow is very bad, to much flow works good but isn't efficient in power used for moving the water.

I really don't see how that simplified matters.

In example one we have high efficiency.

In example two we have a waste of resources (extra drain noise, additional plumbing, more expensive pump, saltcreep, microbubbles, added heat and noise from larger pump etc. etc.). There is a lot more to it than "to much flow works good but isn't efficient in power used for moving the water." Protein skimmers are designed to maintain bubble stability long enough to deliver the "bad stuff" to the collection cup. Once you lower salinity, add ozone, or decrease the concentration of "bad stuff" you compromise the stability with a net result of premature bubble merging and popping (wet foam). This is why protein skimmer must be sized correctly for the tank and subsequent bioload it is intended for. Installing an oversized skimmer on a tank will often result in poor foam development.

In example three we are giving the skimmer a deficit of "dirty" water, and falling short of the manufacturer's feed requirements. Whatever the shortfall is, will be your rate of inefficiency. Unless you are prepared to challenge the skimmer manufacturer's recommended feed amount for a slower feed, you have a net loss of efficiency. Extra passes through the skimmer with the same effluent water that has just been skimmed is not the same as increasing contact time and does not "skim the hell out of the water".

Your math is incorrect in scenario three as well. The skimmer is fed new "dirty" water at a rate of 80 gallons per hour. Providing you agree that a FIFO system is the most efficient, some of that water will be processed once, while other molecules will be processed many times. There is actually a formula for this in Escobal's book that you disagree with.

How can you assume that you are getting "max pulldown" by reskimming the same water over and over at that unknown rate. Based on a feed of 80 GPH and skimmer pump output of 500 GPH, the water will pass through the protein skimmer 6.25 times per hour, providing your design incorporates a way of telling how many times each molecule has travelled through the skimmer before returning to the display A FIFO design can assure that all 80 GPH passes through once, but after that it's entirely random.

Originally Posted by StirCrazy

heaters will work just as good in high flow as in low flow but they transfer more heat to a perticular sample of water in a lower flow, but in a closed system where we have constant cirulation the end result will be the same. and to low a flow can cause heat gradiants which you don't want. as for UV this is a hard one as you have to match the flow written on the UV unit.. mine wanter 400 to 550 gph so I gave it a 550gph pump and knew there would be between 50 and 100gph of losses, chiller same thing match the flow rating.

Heaters rarely come on in reef tanks, but I still install them nonetheless. Debating their maximum efficiency at the cost of the other equipment you will actually use on a daily basis is moot. There is a difference between manufacturer's directions and scientific formulas for zap rates. If you want efficiency, then use Escobal's formula. Here is a simplified version you can follow. http://www.aquariumadvice.com/articl...ers/Page1.html
A typical 25 watt UV sterilizer works most efficiently at 80 GPH throughput.

Originally Posted by StirCrazy

so the way I had my tank set up I created massive amounts of flow in the display to keep everythign suspended. my surface was very turbulant so I never developed bio film that needed to be skimmed off the surface. but I still used a smooth overflow to reduce noise and I had the water flowing over it at a depth of about 1/4" so I would have enough water flow to carry suspended junk to the sump.

Proteins are polar, with one end being hydrophilic (attracted to water/repelled by air) and the other hydrophobic (repelled by water/attracted to air). Protein constantly switch polarity back and forth, so when we collect surface water it is always rich in hydrophobic proteins, or surfactants (surface active agents).

Originally Posted by StirCrazy

from the sump I had one pump tt remove water for my skimmer, this sucked from my settling pond and returned at the return pump chamber, my heaters were located in the settleing pond where the flow was a little lower. I had two pumps pull water out of the return pump chamber and send it to the chiller and the UV then return at the very bigining again to help keep the flow in the bigining section very fast and turbulant so any suspended matter wouldn't fall out befor the settling pond.

the result of this system was very very little cleaning of crap from the bottom of the desplay, but lots from the settling pond which is what I wanted. I would shut down the return pump, skimmer pump and UV pump, suck all the water from the settling area (about 20) then put my new salt water in there and water change and clean up was done. I don't like refuge, algae or anything else in the sump, as they do need a low flow, so I had my refuge remote and I pumped water to it and it trickeled back into the display directly.

Steve

Chaetomorpha and Gracilaria do very well under high flow rates, but it isn't a requirement.

I don't understand why you wanted high flow in your sump? I like the idea of a settling chamber, but it should be slow moving and at the base of the first zone (skimmer/settling/mechanical filtration). Also why not use one pump for the chiller and UV unit? By returning these effluents (UV & chiller) to the beginning of your sump, you are irradiating the water two or more times, and getting a heat gain by not sending the chilled water directly to the tank. It looks like your system is a "water juggler" with a lot of resources expended to complete a simple task. By you description, your sump served two purposes 1) House the protein skimmer. 2) House a settling chamber. The rest of the equipment you mentioned is either a header tank or inline. Why not put the skimmer in the refugium header tank?