Skimmer Op. Bob I have found your column very informative and to the point. Thanks in advance for your speedy response. I have a question on protein skimmers. I understand the important role of these units in marine tanks, but not a lot of people seem to know how one should be operated correctly. I have heard different answers. Should it constantly make foam...should the foam be dry or wet...in a sixty gallon tank, how much waste should be produced if my skimmer is 24 "high and operating with an air stone? I have I have a 3" yellow tang, 3" bicolor angel, two damsels, a few hermit crabs. There is a canister and a wet/dry filtration also. Best wishes, Ben, CA >> Well stated, and thank you for the necessary information. Yes, there are indications that a skimmer is operating "properly", "ideally", "really" on a system. We'll mention the most important two, and then answer your query directly: 1) The foam should be "dry" versus wet. That is just mostly foam, not a bunch of watery bubbles that have spilled over to the collector cup or drain as a consequence of improper water height in the contactor, too large, too many air bubbles, poor skimmer design... 2) The amount of collectant should be variable, i.e. not consistent every hour. There are about two high cycles per day for most types of systems, and your skimmer should show this... more persistent bubbles and gunk collected, with periods of lower amounts in-between. In other words, if your skimmer is continuously collecting whatever it is, it is not "catching up" or removing optimally the fractions you want to be rid of. Q/A) With the bioload and filtration you mention you should have an ounce or so of collectant/waste per day or so... of dry foam that coalesces into a dirty liquid. Bob Fenner 

When to fire over the skimmer  11/23/05 Thanks for all your previous help. I have one more question. When do I add the protein skimmer?. During the cycling process, or afterwards?.............Thanks Bob................................Lou. <I would run it from the get-go. From filling the tank, in most circumstances. Bob Fenner> 

Remora not working? Hi, <Hi! Ananda here tonight as the rain pours down...> I have a 4 ? month 55g setup, 65lbs LR, 50+lbs Southdown sand, AquaC Remora skimmer and two maxi-jet powerheads for circulation.   <Sounds like a nice setup!> I just removed the trickle filter, after reading here it is not really needed, could be a nitrate trap, even thought I have zero nitrates detectable I removed it anyway.   <If you have a trickle filter with bioballs, it's best to remove the bioballs slowly before removing the whole filter. If you remove the whole thing at once, the rest of your system isn't used to handling the whole tank at once, and you'll probably get a nutrient spike.> I have no corals yet, but 4 small fish (damsels, wrasses) and not much of a bio-load, I guess, but I read here I should get a dark cup of skimmate daily.   <Hmmm, yes, in a full-blown system... that is a light bio-load.> I never get a dark cup daily… always a light green smelly tea.  Since I want a cleaner looking tank, I am not sure what to adjust because the collection box is the only thing I can change. <Not quite... see this thread from the WetWebMedia discussion forum: http://wetwebfotos.com/talk/thread.jsp?forum=5&thread=8514> I have tried moving the powerheads in different positions, tried the skimmer powerhead in different heights (switched to an Eheim for awhile) etc… and same results, green tea.  I have also noticed without my trickle filter and all the gunk (brown algae/diatoms?) it was catching daily, is now being spread throughout the tank.  It is much worse than before the mechanical filter was removed and is building an eyesore.  I thought skimmers helped prevent this?   <Skimmers and sufficient water circulation... two powerheads may not be giving you enough cross-current/random current action.> How does one "skim aggressively"  as I keep reading in your recommendations?  It seems like my skimmer is not working properly, but I have tried everything.   I have cleaned it thoroughly and same results.  I don't know what else to try, any help would be appreciated. :-) thanks -Brian <There is a thread in the Equipment forum that includes some good info from JeffM: "Upon trying to figure out why my skimmer was not producing, I ran across many suggestions from AquaC, local fish stores, books and forums. Here they are: 1. Skimmer is new and manufacturing oils may still be present in the skimmer or pump; 2. Clogged air valve from salt creep; 3. Cooking oils or aerosols inside the home may be affecting the water (extreme case); 4. Food supplements, such as Selcon (vitamin C), added directly to the water retards foam production; 5. Dechlorinators that produce fish slime coating may inhibit foam production; 6. Low bio-load, or the water chemistry must stabilize in the tank from the introduction of the skimmer; 7. Fish feedings, carbon changes and water changes may stop foam production between 1 to 8 hours; 8. Riser column is too dirty; 9. The overflow elbow on the riser column (which also acts as the air vent) is obstructed/retarded by an optional add-on overflow device." If none of these seem to apply, do email [email protected] and they can help you troubleshoot. --Ananda>

Skimmer Tweaking I NEVER produce any liquid as dark as coffee from my skimmer. It's always very light colored like light tea. . . what am I doing wrong? <you may not be doing anything wrong.. many types of skimmers and qualities of performance... venturi's are some of the most finicky styles> Please help. I have the type of skimmer that sits inside the wet/dry by the way. <such skimmers can be the most problematic... if they are not sitting in a skimmer box that fills with raw overflow water... then they are at the mercy of the fluctuating sump level which affects the flow rate (head pressure) on their feed pump. This lead to very inconsistent foam production. A simple plastic box/bucket/tub or divider in the sump can fill with water first before overflowing into the sump proper (see http://www.wetwebmedia.com/plumbingmarart.htm). And even with a well made/brand skimmer and ideal inline plumbing... you still need to make adjustments. If the skimmate is too watery, you may have too much air or water flow. My advice is to leave one constant (like max airflow) and then restrict the water on the outflow side to raise or lower the foam/water level in the neck. Lower the level to force dry foam collection or raise it to increase wetter collection> Thanks for any advice you can provide! :) <best regards, Anthony>

Skimmer question Good morning Crew,  Great site guys!!! Just a quick skimmer question. Is it necessary to turn off the protein skimmer when adding things like phytoplankton, iodine, reef complete, etc..? <No, not necessary for additives. Probably not good for the pumps either. Most are designed for constant use and routinely cycling on and off would place added wear and tear onto their motors.> I've heard the skimmers don't distinguish between good or bad "stuff" & will remove the additives also. <This is true, but they remove far more noxious compounds than the few good things. Their benefits far outweigh any potential drawbacks.> Thanks in advance for you response, Craig <You are welcome. -Steven Pro>

Protein skimmer cup cleaning... Okay, now that my TF1000 is working better (due to some minor change in setup), I have a question for you. If I'm dumping the collection cup every 2 - 3 days,  <I wish it was daily> should I scrub down the riser tube like I'm currently doing?  <yes at least once weekly or every time you clean cup> I use a baby bottle bristle brush cleaner to get out all the gunk that has collected on the inner part of the tube. Reason I ask is that I think that I may be limiting the efficiency of the skimmer if I get rid of the gunk too often?  <not exactly...only temporarily do you inhibit it (mere hours). The "gunk" on the inside of the neck severely impedes foam production in as little a 2 days if produced thickly!> The TF1000 manual says that there is a 48 hour "break in" period on a clean protein skimmer for some reaction to occur between the skimmer chamber and air bubbles... and I'm wondering if it's maybe the same for the riser tube. <I disagree with 48 hours... but there is a break in period of a few hours. Most skimmers properly adjusted resume collecting skimmate within six hours> Thanks in advance. <kindly, Anthony>

Yet another Skimmer question Gentlemen - Anthony has replied to other emails regarding adjustments of skimmers sitting in sumps by stating the use of "skimmer overflow" boxes or dedicated chambers for the skimmer to sit in. His referenced diagram was helpful in describing this set up. He described the box as a location to send raw water into so that the pump would have a constant level to draw from. This set up seems to be for skimmers with submersible pumps. Does this box system work for skimmers with external pumps? <Yes> I have an ETS Evolution 750 skimmer being fed with an Iwaki RLT 55 pump. This skimmer is placed in the sump raw and skimmed water is pulled from the sump by the pump to the skimmer. Another pump pulls out of the same sump back up and returns to the tank. I get very thin skimmate like watery tea and have never really had any nasty stuff from the skimmer. I thought with an 165gal with a 3" Picasso trigger, a 3" clown trigger, a 7" shoal tang, and a 6" harlequin Tuskfish that I should be pulling more nasty gunk from the skimmer than what I am getting. <Agreed> I have about 140lbs of live rock with an aragonite substrate and only a few sparse mushrooms. I was told by AE Tech that I was pushing too much water through too fast and not allowing the foam to produce. So I have turned the flow down of the pump and am starting to get some better foam production. However, the outflow of the skimmer empties back into the sump which does vary in water level from time to time. Would placing the skimmer, and its outflow, in an overflow box regulate the back pressure of the water flow to produce more consistent results? <It is not the outflow that you should be worried about. It is the variation of head pressure from where the skimmer pump draws water in.> The skimmer water would empty into the box and then overflow back into the sump. This would allow the sump level to fluctuate but not the level that the pump is working against. Would this be correct? <You want the skimmer pump to draw from a surface skimmed source and for that water to be held in a chamber at a constant height.> Thank you again for all your time answering questions. Steve Morvay <You are welcome. -Steven Pro>

Skimmer Hook Up Hi Bob, Thanks for the previous help. I have a quick question about hooking up/plumbing protein skimmers, namely the T1000 and the ETSS Super Reef Devil. I believe I saw on your site that the T1000 requires connecting an overflow directly into the skimmer. Is this true, and if it is true, wouldn't it be hard to adjust? <Mmm, not true... can be hooked up to system or a sump... Not as hard to adjust as many other makes, models... but better to situate in a setting where the pump/discharge water level varies little (i.e. if in a sump, refugium setting, where a barrier assures constant water level...> Also, how does the Super Reef Devil compare? I understand they utilize two completely different mechanisms of skimming, but what difference in skimming efficiency, noise, hookup, and power consumption?  <The SRD is for much larger and/or systems where "more efficiency" in skimming is desired. By comparison the Aqua-Medic product removes less skimmate per pass, but is far more quiet and requires much less pumping and energy> I know you are not a fan of ETSS, but this model claims it is pretty efficient, only using a Rio 1800, and it appears this skimmer just sits in the sump and does not require extra plumbing and would be sufficient for a smaller to medium size tank. <Yes, all valid points. A good unit... once again, by contrast, needle wheel makes (Aqua-C, Euro Reef for instance) are even more efficient... per dollar invested up front, ongoing...>  For reference, the skimmer would be for a 125g LPS (primarily) tank with light to medium fish bio load. Thanks for the help, sorry to bother you again. <Never a bother... and a good opportunity to present pros/cons of various makes/models of skimmers. All mentioned are fine products, suitable for aquarium use. Bob Fenner>

Skimmer operation Am new to this, have read much, but have not seen the answer to the following anywhere: I have a 2-3 month old 110 G FO+LR tank, with only 7 fish so far, with wet/dry & skimmer. The skimmer is VERY large (sized for ~200+G), as I plan to remove the wet/dry later on. I know the operation of the skimmer may change as I add more fish, etc. So far the skimmer seems to work for a day or 6 to 7 hours as I expected, generating a stiff dry, brown/tan foam. Then it may just churn water for much of the next day, then start foaming well again. Sometimes it produces a lot of a very wet foam in between. Also I seem to observe that if the salinity or pH is increased, the skimmer foaming gets better--Am I imagining this? Should skimmers produce the dry foam virtually continuously eventually, or will it always vary day by day? <Your skimmer will vary it's output greatly according to water content, bio-activity, additives, chemicals present, etc. Eventually it will probably settle into a more predictable routine, as your tank and your maintenance habits also become more stabilized. A 2-3 month old tank is still settling, believe it or not. And as you add life, rock, and remove other filtration systems, your skimmer will certainly react in different ways. Regards, Lorenzo>

Re: Mexican Turbo Snails, Skimmer Production No way my skimmer will produce a cup a day.  <an all too common reality, my friend... as common as nuisance algae problems> Either I don't have enough in my tank to skim or my skimmer is inadequate.  <it is not even remotely possible that you (I or most any other aquarist) don't have enough to skim. There are systems with precision skimmers that are well made and/or well adjusted that have few if any fish and no supplemental feedings that still skim daily (products of respiration, fecal pellets from gastropods on diatoms, etc). And so... if you have coral or fish that get fed even just a few times weekly you can easily get daily skimmate. The lack of doing so in just a few short weeks builds DOC levels high enough to feed nuisance algae blooms. Your challenge is to adjust the skimmer optimally if you have a good skimmer design. Even the best skimmer needs to get water from a very stable pool: for hang on skimmers the tank water level must be kept extremely stable with daily evap top off and the pump that feeds the skimmer should draw from an internal skimmer box or as close to the surface as possible. Skimmers fed by pumps sitting several inches below the surface of water (sump or display) are really under performing. Proteins are concentrated in the very fraction of an inch of the water surface. For sump model skimmers, they should always draw from a skimmer box (vessel or sealed dam in sump) and never from the open sump with a fluctuating water level. Once this has been established, the neck needs to be cleaned several times weekly when the cup is emptied. When all is said and done though... if you have a Prizm/Red Sea or Seaclone... don't bother. NASA engineers can't get them to work and they are wiser than I am. Invest in another skimmer if necessary. A good skimmer is one of the most important investments in a marine aquarium... and the lack of a good one has frustrated many aquarists terribly... driving some out of the hobby for water quality problems> Since I have the algae problem, it is probably the latter. My skimmer is a Red Sea Berlin with a Mag7 pump. I know these are not considered very good by lots of people. <yes, my friend... public opinion is overwhelmingly unfavorable on this unit. Skimmers should be low maintenance and such skimmers as the above listed models work marginally at best with daily attention> Sounds like I need to look for another skimmer. <you will enjoy the hobby on a whole new level once you employ a good unit. Euroreef and Aqua C get my votes for top of the line and low maintenance> My salt brand is Instant Ocean.  <excellent...tried and true> I run PolyFilter and carbon.  <interesting and agreed> The filter color does not indicate any metal contamination.  <glad to hear it> I am pleased to know that is not my temperature. Seems I am left with improper acclimation.  <alas... perhaps yes. If any consolation... snails and shrimp are extremely sensitive to acclimation> If I decide to try more of these, I will acclimate even slower and for a longer period. Thank you for your time. Greg <best regards, Anthony>

Skimmers I have a Berlin reef system with LR and protein skimmer. If say, a skimmer stops working, how long can I reasonably expect my water quality to be within safe parameters? <Hard to quantify. Your water quality will begin to degrade immediately, as all the crud that is usually being removed, is staying in the water. I guess your question is, when will this degradation become critical. Probably over the course of several weeks to months, with first noticing increases in nuisance algae, slower growth, poor polyp extension, etc. Basically, your corals and fish will begin to tell you if you know what to look for. -Steven Pro>

Skimmer question part 2 (operation) Hello, in response to your response (thank you), if I purchase an Aqua C Remora protein skimmer and position it so the pump portion sits in the first chamber, and the water return portion into the second chamber (they are separated all the way down to the bottom of the tank), would this work well <hmmm.... I think it would work fine>> and not risk the stratification of proteins? (I do not know what that means but it sounds bad).  <ahhh, yes... very simple my friend. Proteins accumulate in the very top most layer of water (like sea foam on the sea). Our goal is to skim (via overflow) and concentrate them for handling by a skimmer. Ideally this means that they should overflow or be carried raw into the skimmer feed/pump. If instead we allow them to crash into a primary vessel (chamber one) before overflowing to a secondary chamber with the skimmer (number two) then the proteinaceous matter can migrate to the surface of chamber one and get partly bypassed. Essentially... we are looking for a direct path of raw overflowing water to the skimmer> I prefer not to have to drill a hole into my tank. In your opinion, does the Remora (pro or regular) work as well or better than the CPR Bak-Pak's?  <yes. as well or better for the Aqua C IMO> Thank you again for your help. Steve. <best regards, Anthony>