By Bob Goemans
Site Supported in Part by:
Two Little Fishies 

AquaC Protein Skimmers - Second Generation Models

Manufactured by: AquaC

A product review by Bob Goemans

Product Review ­ AquaC Protein Skimmers - Second Generation Models

(Written in 2002)

This is my third test of different AquaC (1) skimmer models and both prior units were of excellent leading edge designs. The same is true of this 'second generation' model, the EV 240, which contains 'significant' improvements.

I met the owner of AquaC, Jason Kim, at his product booth a few years ago at a MACNA event. I was especially intrigued with his new and unique spray nozzle technology (U.S. Patent #6,156,209). Testing of first generation EV models (there were three models ­ EV-90; EV-150; and, EV 200) proved its technology was extremely efficient and overall design was more than capable of performing as advertised. About a year later the spray nozzle technology was incorporated into a hang-on-the-side skimmer called the Remora. I tested the larger of the two models, the Remora Pro, and found it to be the best of all Hang-On-Tank (HOT) skimmers at that time frame. I say that time frame only because there are some new brands of HOT skimmers on the market at this time and I don't have any information/feedback on their performance. But I doubt they can compare efficiency-wise with the Remora units.

When Jason recently contacted me and asked if I was interested in testing a second generation EV, of course the answer was 'yes.' I wanted to see what improvements could be made to an already very efficient product! He sent me an EV-240, which is one of six new models - an EV-120 that stands 18 inches high. Its footprint is 4.5 x 8.5 inches and is priced at $299. The EV-180 stands 20 inches high and its footprint is 5.5 x 9 inches and is priced at $339. The EV-240 stands 26 inches high and its footprint is 6.75 x 10.75 inches and is priced at $399. The EV-400 stands 32 inches high and its footprint is 6.75 x 10.75 inches and is priced at $479. The EV-1000 stands 32 inches high and its footprint is 9 x 12 inches and is priced at $649. The EV-2000 stands 42 inches high and its footprint is 9 x 12 inches and is priced at $799. It would behoove those interested to visit the AquaC website and review the various brand and model optional pumps recommended for these models, along with their wide range of operating parameters.

The well-packaged EV-240 unit arrived safe and sound and included an extensive user's manual. It was removed from its shipping container and is constructed of high quality cell-cast acrylic with high quality fittings. All edges were smooth and appear flame polished. At the time of arrival I had a friend wanting to try a more efficient skimmer on his system and 'volunteered' to test the unit. I couldn't agree more that his system needed a larger skimmer, so agreed to set it up at his home.

The User Manual fully explains how these skimmers can either be used in a sump or as a stand-alone unit. For the purpose of this test the unit was placed outside the sump and one pump, a SEN 90 (2), placed in the sump. The spray nozzle was connected with a short piece of clear flexible tubing to the outlet fitting of the pump. Another piece of tubing connected the unit’s 1.5 inch gate valve to the sump. When that was finished, the gate valve, which came already connected to the skimmer body, was fully opened. (I should note the two smaller models have a 1 inch gate valve, the middle two contain a 1.5 inch gate valve, and the two larger units come with 2 inch gate valves.) The pumps electrical cord was plugged in and water flowed into the skimmer. The gate valve was slowly closed until the skimmers internal water level reached its recommended level. This was just below the air-mixing chamber at the top of the main skimmer body. The supplied automatic waste container was then hooked up to the drain fitting in the collection cup and the unit was completely set up and running! That took less than fifteen minutes.

As with all AquaC's skimmers, gravity returns the unit's processed water to the sump. Therefore the unit's internal water level needs to be above the water level to which its flowing into. If it's the sump, its water level needs to be below that of the skimmer's outflow gate valve. This is fully explained in the User's Manual. One of the new 2002 model improvements was to elevate the gate valve on the side of the main body so that it can sit in sumps as deep as nine inches without being elevated. The addition of a precision made ball valve for airflow is another improvement over that of the older models and allows for precise air adjustments. Older models had no airflow control and it simply entered through a space between the foam collection cylinder and main body. That led to salt creep in that area which required cleaning from time to time. Now, that's a thing of the past! And the injector spray nozzle is more easily removed than on first generation models should servicing ever be needed. And its cleaning is something I doubt will ever be required. This injection nozzle is internally shaped quite differently than normal venturi or Beckett fittings. It has more openness for water to flow through, therefore small limpet snails/other type crustaceans would rarely, if ever clog it, as they do on Beckett and other type venturi fittings. AquaC's air injection nozzle is extremely efficient and quiet, and can easily be considered more maintenance free than anything else on the market.

Another striking improvement is the 'Twist-Lock' flange connections that separate the collection cup from the main foam collection cylinder and/or its cover. No more nylon thumb screws to fuss with! Simply twist the collection cup or its cover and it easily separates. Between each surface is a gasket that assures a leak proof connection. I should note that only foam extends into the main cylinder, as the unit's water level does not need to extend into the main cylinder as with other type skimmers. So the Twist-Lock feature remain a very functional improvement.

One of the more interesting improvements is the addition of a John Guest fitting near the air control valve. This fitting is standard on 240 and above models. An optional item costing only five dollars on the 120 and 180 models. This is a small fitting that allows a plastic tube, like that of an airline, to be inserted and firmly held. In fact, that's exactly the purpose of the fitting, to allow a calcium reactor effluent drip tube to be connected to the skimmer. This would allow for the low pH of its effluent to be raised by blowing off excess carbon dioxide before the effluent enters the aquarium. An ideal situation! The John Guest fitting could also be used for connecting ozone if needed, as the entire skimmer is ozone safe. To release the tube, simply press down on the fitting's small ring that holds the tube. Could not be easier and AquaC is the first to utilize such a useful fitting in their skimmers. I should also note the Guest fitting is removable, simply unscrew if it ever needs cleaning. While making different water and airflow adjustments during the test I became aware the even if water level rose into the foam collecting cylinder, which is higher than the Guest fitting, it would not run out of an open Guest fitting! The air pressure/space in the top of the main body unit simply remains while the unit is running and prevents any water from coming out of an open John Guest fitting.

Purchasing an optional Auto-Waste Container is highly recommended. It is equipped with an anti-siphon assembly that uses a Ping-Pong ball. Should the container fill with wastewater the ball floats to the top of the assembly and blocks airflow out of the container thereby effectively creating a blockage that stops any flow of water into or out of the skimmer. The 'Twist-Lock' top of the waste container, also fitted with an EPDM gasket, is a snap to remove. It has a small cylinder-shaped chamber on its top surface that can hold a bag of activated carbon that will prevent any objectionable odors from escaping. All incoming skimmer air exits though the container's air filter. The Auto-Waste Container cover can be removed while the skimmer is operating so the container can be emptied as needed. Even the top of the collection cup can be removed while the skimmer is operating for easy cleaning. There are two sizes, 2.5 and 5 liter.

As for flow design, the pump forces water through the injection spray nozzle. It strikes the water surface just below air mixing chamber creating a less than atmospheric pressure gradient. The fresh air supply is controlled with the ball valve. The spray effect from the nozzle mixes a huge quality of air with the incoming water and produces 'extremely' fine bubbles.

Flow of the water and its bubbles is carried downward into the lower portion of the main skimmer body where angular deflection panels separate bubbles from water. These second-generation models have redesigned baffle plates that greatly reduce any possibly of fine bubbles reaching the aquarium. In fact, there were no bubbles, not one entering the sump! Another very good improvement. These baffle plates cause a rotation of the water and bubbles, adding to bubble dwell time and their ability to pick up additional dissolved organic compounds. The collecting foam then rises into the bottom portion of the clear acrylic cylinder-shaped foam-collecting tower that is attached to the top of the main skimmer body. The foam eventually rises and empties into the unit's removable collection cup. Of course, the water drains out of the main skimmer body through the gate valve back into the sump.

The amount of air and water these protein skimmers process is extremely impressive. For something so small their performance equals other brand skimmers that are much bigger and more expensive. Also worth noting is the size of their air bubbles, which equal or better those produced in many skimmers using needle impellers or Beckett fittings.

The dark gray, yet transparent main body of AquaC skimmers is another feature worth discussing. All other brands of skimmers that have a box-like main body are made from clear plastic or opaque material. Clear material can encourage algae growth, which can be a maintenance chore if placed in a lighted area. Of course, opaque material does not allow the hobbyist to view its interior and results in guesswork should something unforeseen occur. That won't happen with AquaC protein skimmers. However, inner walls and baffle plates are difficult to reach, yet they would rarely, if ever need cleaning.

After two weeks of operation it was time to evaluate its performance. Overall, we both were highly impressed with its performance. The Twist-Off features reduced cleaning time, the slightly larger main bodies of these second-generation models process more water than older models, and the John Guest fitting is a superb addition. The controllable air flow ball valve is also a major improvement and totally eliminates salt creep. So is the addition of automatic waste containers, an optional piece of equipment but well worth having.

There may be a couple of areas that could use some improvement. The first would be a cap or plug that could be used to prevent air from entering the skimmer through the John Guest fitting if not being used. If the hobbyist chooses not to use it, air enters and seems to make the initial adjusting of the air control ball valve somewhat more sensitive. However, once set, it did not affect the gate valve setting thereafter and water height remained very steady. Simply placing a piece of tape over it took that sensitivity out of the set up equation. But a cap or soft material plug might be a nice addition to the base unit. A second possible improvement would be a removable handle on the collection cup cover. Griping the narrow thickness of the cover and twisting to remove is somewhat awkward.

All in all the AquaC protein skimmers rank among the best I've ever tested and all AquaC skimmers come with a 90 day warranty. Visit their website, as there is a growing array of products and contact them with questions.


1) AquaC, 7965 Silverton Avenue, Suite 1314, San Diego, CA 92126, phone/fax 858-689-1121,

2) Won Brothers, Inc., 11050 F Livingston Road, Fort Washington, MD 20744, (888) 417-6969, fax (888) 749-6750,

More Reviews
Site Supported in Part by: