Who rates skimmers

[Gizmo]

Just an off the cuff though, could you not rate a skimmer based on ml/hour of "dense" skimmate (i know dense is a relative term) so at least all skimmers are on a level playing field. You could then calculate how many ml/hr you would need based on your bioload and needs. (no I don't know what that calculation would be, but it wouldn't take much other than experimenting with a baseline skimmer, and varying bio-loads to come up with an approximation)

[sphelps]

Originally Posted by Gizmo

Just an off the cuff though, could you not rate a skimmer based on ml/hour of "dense" skimmate (i know dense is a relative term) so at least all skimmers are on a level playing field. You could then calculate how many ml/hr you would need based on your bioload and needs. (no I don't know what that calculation would be, but it wouldn't take much other than experimenting with a baseline skimmer, and varying bio-loads to come up with an approximation)

I wouldn't want to be that sales guy trying to sell those skimmers
Simpler is usually better and specifying specifics like that will cause huge issues as results will always vary. It's one thing to say this skimmer will typically handle 200 gallons of tank volume but to say this skimmer will produce X amount of skim mate is another story. There are certainly skimmers out there that have bad ratings, seaclones are one that come to mind, but good quality skimmers are rated fairly decent in my books, and on occasion some manufacturers do actually give a few rated volumes based on high and low bio-loads.
I think too much thought is going into this, consider all the variables involved in actually determining the right skimmer. Amount of fish and other livestock, size of fish and other livestock, type of fish and other livestock, amount of food feed, allowable nutrient level (sps-low, lps-med, fowlr-high), tank volume, and so on. I mean these ratings are just general guidelines, just like fuel ecomony ratings on cars, they aren't that accurate either but there are too many variables involved for it to be accurate for each person.

[banditpowdercoat]

One thing I know, BOTH my skimmers suck, and Im to broke to get BK's LMAO

[fkshiu]

Tunze gives you a little more help by listing a "maximum" tank size for their skimmers which you subtract down from depending on what you are keeping in the tank (e.g. SPS, LPS, softies, FO).

[mark]

little dated and yes could be problems but here:

http://www.aquariumcontrollers.com/a...p#skimmerchart

[lastlight]

Best they can do is give you ballpark ideas and then you ask people who have experience with them I think.

[untamed]

I'm recalling that study that recently tried to measure WHAT was being removed by skimmers and how quickly various models removed it.

I believe that their conclusions were that the "larger" skimmer (the one the processed a larger volume of water per hour) removed the measured stuff more quickly, but that all the skimmers tested reduced the measured stuff to about the same level given time.

It struck me that a big difference between the test environment and an actual aquarium is that the aquarium continually generates new waste so a truly undersized skimmer won't ever get the chance to catch up and waste could accumulate.

Yes, I agree...it is more about bioload than actual water volume.

IMHO, size matters. In order to increase the amount of water it can process per hour, the chamber needs to get bigger. Increasing the flow rate with a smaller chamber just reduces the amount of time the water is in contact with the air bubbles (dwell time). In my case, I wanted to get to 1.5x tank volume per hour (600gph) with 2 minute dwell time inside the skimmer. That means that I need to have a 20 gallon chamber....yikes!

After that, I didn't really pay attention to what the skimmer says it is rated for.

[golf nut]

BK will tell you in a heartbeat that you can overdo skimming by buying a unit that is oversize, it simply doesn't work, or should I say doesn't work properly.

I know there is a distinct difference between having the skimmer in the tank with no sump as compared to having a sump with a 10 times turnover, it just isn't the same, the tank install though ugly will work better every time, explaining it is a different matter.

[robert]

Brad - I like your theory, it makes sense to me. I have a question though. Which of those 2 parameters is more tweak-able/forgiving - tank volume per hour or dwell time?

For example, I have ASM 5G with about 6gal cylinder capacity. Manufacturer suggested system size for this one is 700gal. Granted, real life users would not put this skimmer on anything bigger than 350-375gal. Now, applying your theory, keeping flow at 1.5x volume of the tank with 2 min. dwell time this skimmer is no good for anything bigger than 120gal. Which parameter would you tweak for bigger system? Volume per hour or dwell time? No, "Get a bigger skimmer" is not applicable answer at this time.

Thanks a lot.

Cheers.

Originally Posted by untamed

I'm recalling that study that recently tried to measure WHAT was being removed by skimmers and how quickly various models removed it.

I believe that their conclusions were that the "larger" skimmer (the one the processed a larger volume of water per hour) removed the measured stuff more quickly, but that all the skimmers tested reduced the measured stuff to about the same level given time.

It struck me that a big difference between the test environment and an actual aquarium is that the aquarium continually generates new waste so a truly undersized skimmer won't ever get the chance to catch up and waste could accumulate.

Yes, I agree...it is more about bioload than actual water volume.

IMHO, size matters. In order to increase the amount of water it can process per hour, the chamber needs to get bigger. Increasing the flow rate with a smaller chamber just reduces the amount of time the water is in contact with the air bubbles (dwell time). In my case, I wanted to get to 1.5x tank volume per hour (600gph) with 2 minute dwell time inside the skimmer. That means that I need to have a 20 gallon chamber....yikes!

After that, I didn't really pay attention to what the skimmer says it is rated for.