View Full Version : So you want to buy a skimmer

Larry M
10/26/1999, 05:46 PM
This is an ongoing series for our archives, created to answer some of the common questions we have when we first get into this hobby. Already in the archives are threads on filtration and starting a reef aquarium in general.

Some of the questions we all hear regarding this, and probably asked one time ourselves: (You don't have to answer every one)

Do I even need a skimmer?
Can I save some dollars and buy something to get by for now, then upgrade later?
Are the manufacturers telling the truth when they say this skimmer is rated for x number of gallons?
How many types of skimmers are there and what is the difference?
Can I make my own?

Have at it!

Larry M

Visit Reef Central's Home Site at:
www.reefcentral.com (http://www.reefcentral.com)

10/26/1999, 08:53 PM
Okay, I'll try.

1. Do you need a skimmer?

Let my give a little info on my situation first. I like to keep a very high bioload in all of my tanks. I have what many would call too many fish and corals in my tanks. After saying that, I feel that a skimmer does help me a great deal. I keep tanks both with and without skimmers and have found that the skimmed tanks are much more forgiving. If I overfeed the tank the skimmer takes care of it for me. I have less algae problems and the water looks cleaner on the skimmed tanks. Not to say that algae problems are non existant but I believe that the skimmers do help keep it from taking over. I am trying to keep a small nano tank without a skimmer by doing water changes but have been having some major problems with algae an sick fish. These problems may be caused by the small amount of water in the tank and unstable water enviornment though. If I could put a skimmer on the nano I would. I also kept my first 29g tank without a skimmer for about six months after I started it and once I added a skimmer the water quality improved greatly and fish loses decreased. In my showtank using the large DownDraft skimmer I am able to feed very heavily and change very litte water without any noticable water quality problems. BEWARE BEWARE BEWARE - Do not take this as a recommendation to overload your tank and not change water like I do just because you have a large skimmer. I use other means of filtration besides my skimmer but I am saying I would not try to keep the load that I have without a large skimmer on the tank.

2. Can I save some dollars and buy something to get by for now, then upgrade later?

I would say no. I have tried this and ended up spending much more money in the long run. My $300 ReefDevil actually cost me $600 because of all of the other skimmers that I threw away. IMO, get the best skimmer from the start and keep the money you save for livestock instead of buying junk that will end up in the garage or trash.

3. Are the manufacturers telling the truth when they say this skimmer is rated for x number of gallons?

I would think that most manufactures are telling the truth based on a specific load. If you have a skimmer rated for 60 gallons on a 60 gallon tank with no fish it has a good chance of meeting your needs. If the same 60 gallon tank is loaded with 12 fish the skimmer may be underpowered. The manufactures do not give enough detail on how they come up with the capacity ratings. I use CPR backpacs (rated up to 60g if I remember correctly) on both of my 29 gallon tanks and one is cleaner than the other because of the differnt bio-loads. I myself like to use an oversized skimmer on my tanks so that I have room to grow.

4. How many types of skimmers are there and what is the difference?

Here are the three types that I have used on my tanks.

Counter current - Most CC's consist of a pastic tube, airstone, and air pump. I have used the small in-tank type CC skimmers and have not had very good luck. I had a hard time adjusting them and the airstones got plugged quickly. I have heard that there are some very large CC skimmers that work very well but they are hard to maintain, need large airpumps and do not look good in the living room. One advantage is that they are supposed to be more plankton friendly and do not kill off the good critters like some of the other types can. Many reefkeepers swear by CC skimmer have very successful tanks to back them up.

Venturi - This is another type of skimmer which uses a powerhead or pump and an air intake to create the foam. The combination of the venturi air intake and the water pumped into the skimmer column creates a large amount of bubbles. These are fairly small in size and work well on most tanks. They are cost effective, come in many different sizes and are popular with many reefkeepers. They are maintained by cleaning the pump every so often and once adjusted are fairly stable once the correct water level in the riser tube is set.

DownDraft - Skimmers of this type are very powerful and skim very well IMO. An extreme amount of water and air is mixed together to create the foam. Because of the amount of water flow needed a very large pump needs to be used. Because of using such large pumps your electric bill will suffer and chances are that some heat will be added to the tank. As far as operation the large pump pushes a great deal of water through a tube of bio-balls. The tube that contains the bio-balls also has an air intake. The amount of water moving through the tube creates a large amount of suction and pulls in a huge amount of air. This air and water mix combines to create a very efficient unit in a somewhat small package. The only disadvantage that I have found is that they are somewhat hard to adjust when first setup but do become stable after time. It is also believed to kill plankton and other small critters because of the very powerful pumps used. FWIW, This is the type of skimmer that I run on my 75g show tank.

There are a few other types of skimmers available such as the HSA which uses a fountain spray jet to create the foam but I have not used these myself. It is said that HSA's work as well as DownDraft's but use a smaller pump. I cannot comment on these because I have never used them.

5. Can I make my own?

I am sure that many great DIY skimmers can be made at a great deal of cost savings but I would just end up flooding my house. :)

Remember your results may vary.




[This message has been edited by Doug (edited 10-26-1999).]

10/26/1999, 11:10 PM
Radio talk show hosts bring up the death penalty and abortion when there's not too much conversation going on; skimmers are the reef equivalent. Here's my worthless opinion:

Do I even need a skimmer?
Need? No. But it's a darn good idea. We do so much to make our reefs work, why stop at the single most effective piece of equipment? Lighting and skimming are the best expenditures you can make. The ocean uses a skimmer, why shouldn't hobbyists?

Can I save some dollars and buy something to get by for now, then upgrade later?
Kind of. I'll get killed for this, but I started with a SeaClone which worked well. Don't go for the really low end stuff that makes noise but little or no foam. After the SeaClone, I upgraded to a Berlin HO. The Berlin is way better.

Are the manufacturers telling the truth when they say this skimmer is rated for x number of gallons?
Rules of thumb only. It all depends on your setup, bioload, etc. The CPR Backpak II is rated up to 60g. I know people happy with it on their 55 and 50g tanks. Accurate enough.

How many types of skimmers are there and what is the difference?
Doug gave a synopsis of the types above.

Can I make my own?
Sure! It's easy IF you are handy that way. Just like computer generated art is easy IF you have the artistic talent already. I've seen people who can make them and save a lot (after all, it's just some plastic arranged in a particular way), but for commoners like me, it's worth paying for a manufactured one.

10/26/1999, 11:55 PM
How many types of skimmers are there and what is the difference?

I'm adding the aspirating skimmers to the types of skimmers list.

Euroreef, DAS, and Turboflotor are the only aspirating skimmers I'm aware of. IME, the aspirating skimmers (I have a Euroreef) produce smaller bubbles than any other method excepting perhaps CC air skimmers. Also, they use smaller pumps than the downdraft and venturi skimmers. Roughly put, aspirating skimmers use a modified impeller that is covered with small plastic pegs to shred the water/air mixture, thereby producing very fine bubbles. BTW, the Euroreef and DAS skimmers use a similar peg configuration, whereas the Turboflotor (by far the least expensive of the bunch) uses a different peg orientation.

The HSA/Foam Jet skimmer is, technically, a venturi skimmer and requires a high power pump.

Larry M
10/27/1999, 07:19 AM
I'll put in my own two cents. Do I need a skimmer? If you are asking the question, yes. My opinion is everyone starting in the hobby should have a skimmer. People like me should have a skimmer too, since I like to feed a lot, sometimes put too many fish in my tanks, and aren't totally aware of what it takes in terms of alternatives to replace skimming. I tried going skimmerless on a nano reef for a short time (3-4 months) and I didn't like the results. Also, I feel a skimmer helps provide a higher level of oxygenation. I'm aware that some people do not use a skimmer and have healthy, beautiful tanks. I applaud that, I just don't feel it's a method to start out in this hobby using.

As for brands, here's my bias on that: I have used and liked the Berlin Red Sea, the ETS Reef Devil, the CPR sr-4, the Sanders air driven Piccolo (very small tanks only). I have not used the Turbofloater or the Sipedon, but they have excellent reputations. So do Lifereef, Tunze, and some others for larger tanks.

I think you can make a better skimmer than you can buy. But, it may not be cheaper because you will probably make two or more to get one that is just right. And, when there are so many good ones on the market, spending the time on this doesn't seem worth it to me.

Good luck,

Larry M

Visit Reef Central's Home Site at:
www.reefcentral.com (http://www.reefcentral.com)

10/27/1999, 10:01 AM
i have been in this hobby for only 6 months. my first salt water tank was a nightmare for the first month or so. i started with a canister filter and no skimmer. everything i put in that tank died. (all damsels)the ammonia buildup was horrible. i was doing 1/3 water changes every couple days just to keep any fish alive . then i went back to the petshop mostly complaining about how this hobby just sucked .(not that i could have been dragged away from it even then).they sold me a protien skimmer a sea clone, which did help one thing about sea clones (hang on type)hoses can come off very very easy spraying water all over the house .you have to be very careful about that. i ended up having to do alot of adjusting to get very little foam and at first it was very noisy. i would not recommend this skimmer to anyone though i have heard it is better with smaller systems.
changed over to a big mumbosa and it works better, but not that great. it needs to be adjusted quite a bit. i dont think i would get another.
i just got a a excaliber skimmer .i love it . it skims like you would not believe .i do not have to adjust it at all .this time around the cycling is going very smoothly and part of it is i have a relible skimmer.
if you can get the best skimmer you can get. it saves alot of headaches and alot of fish.

i have heard wonderful things about turbofloters .the pet shop i know uses it and it seems to be working well for them.

would i try a tank without a skimmer maybe when i have more experience but i would not try to do it now i need the flexibility it gives me .hope this helps

: )

10/28/1999, 02:26 PM
1) Do I need a skimmer: IMO you do not need a skimmer, in fact skimmers do a lot to destory the fauna in the tank and remove life that is very important for a properly functioning reef. They also remove food sources for deep sand beds. That said, I NEED A SKIMMER, b/c like so many other reef keepers I like to feed my reef and my fish (which makes up for the loss of food sources from skimming). It may be the single most helpful pieces of equipment for maintaining water quality-removing organic phosphate/carbon sources, some particulate matter, and most of all providing oxygen for the tank.

2)Can I save some $$ now and upgrade later. The question answers itself b/c like so many of us-you will not be saving dollars by buying things more than once, in which case the old skimmer ussually goes in the box with the rest of the save a dollar items.

3) Are the manufacturer's telling the truth when they rate a skimmer? I can not tell you where they get their ratings from nor can I believe that anyone else can. What levels of proteins are they measuring? No skimmer can get it all the protein out by the physics of the process. So what is it that these manufacturers set as their goal of attainment and is it standardized? We all know the answer to that is no-it is an arbitrary definition defined by the manufacturer. Results will vary on every tank taking into account a number of chemical, physical, and biological factors.

4) Types of skimmers and their differences? I thinkthis has been pretty well defined. Look for a model that gives you the greatest input of air in a small bubble size and greatest contact time for the $$ you plan on spending and you are on the right track. For counter current remember that a pump rating for air input is at a given depth/pressure and skimmmers are a high pressure environment so you will not get the rated air input.

5) Can I make my own? If you have basic DIY skills and a nearby home center you can make a very efficient skimmer that can rival that of commercial skimmers. But as Larry pointed out, sometimes you will not save money b/c you will make and remake a skimmer. My advice to avoid this would be to search and research plan and replan commercial and DIY skimmer designs. And after you do that measure and re-measure all the openings and cabinet space that you have to put the skimmer into. Alot of pre-planning will save alot of hassles.


Larry M
11/09/1999, 04:51 PM
Are we ready to file this one in the archives?

Larry M

View a list of RC Member's websites at:

11/09/1999, 10:15 PM
I dont think theres much left that hasnt been covered unless someone actually listed by name the skimmers that don't work(slander bait)

I reefed,so I spent,it would have been cheaper to do it right the first [email protected]