Reef Octopus Auto Waste Collector

Waste Collector


Most of you know that I have a special affection for products that you may have never even known existed and then once you have them, you wonder how you ever lived without them. This week I got to setup another one of those products, the Reef Octopus Auto Waste Collector.

The waste collectors come in two varieties, a 4” and 6” model. I used the 4” model which has a maximum capacity of about 1400mL (just shy of 50oz). The larger 6” version comes in at a massive 4300mL/145oz capacity (that’s more than a gallon!).


Here are the basic specs:

Model # OCT-WC100 OCT-WC140
Waste Collector Diameter 4” 6”
Waste Capacity 1400 mL/49 oz 4300mL/145oz
Footprint: 6.5”x6.5” 8.3x8.3
Height 18” 21.75”
Skimmate Input Barb Height 12” 16”
Power Cord Length

Wall to Outlet Box: 8ft

Outlet Box to Collector: 6ft

Wall to Outlet Box: 8ft

Outlet Box to Collector: 6ft


For those of you who haven’t seen these or similar models before, they look like an odd combination between a skimmer collection cup and a reactor. The waste collectors are designed to accomplish a few different purposes. The first is to act as a collector for your skimmate. They have an input barb on top that you connect the drain line of your skimmers collection cup to.

Your skimmer skims away and as the skimmate collects it drains down into the waste collector. The waste collector itself stores the skimmate in its collection chamber. Here is where things start to get interesting. The collection chamber itself vents upwards, past a ping pong ball (I know how that sounds and don’t worry, we will get to this later), then up through a carbon chamber before exiting. By running the air through the carbon first you’re going to remove the smell. If your house works anything like mine, its a great step at getting approval from the significant other.

A quick note about carbon: There are a lot of different types of carbon around from bituminous, to lignite, and carbons like our ROX .8 carbons. When it comes to aquarium use (in water) and carbon, the ROX .8 is superior by far. That is followed by lignite and bituminous carbon, with bituminous carbon being the worst performing. Outside and even inside the hobby bituminous carbon is the most common because of its attractive cost to manufacturers but it happens to be the least effective in the tank because it is mostly made up very small pores. Its primary purpose is generally for filtering air and as a result it is low cost and what most aquarium carbons are made out of and usually comes in the form of large pellets. While this isn’t so great for aquarium filtration compared to other types, in this particular application is exactly what you want here because were trying to filter air! Don’t spend the extra money for lignite or ROX here, as the bituminous will be the best served to begin with. It also works out that bitumninous carbon is usually found in large pellets as they won’t fall through the holes.

waste collector pin reef octopus

We all know redundancy in the aquarium is important and while this might not be the place you expect to find it, the collection container itself also comes with a few forms of redundancy. First up is the ping pong ball! The ping pong ball in the setup is actually used to actuate a small pin that acts as a valve. When the collection container fills up the ping pong ball floats up and pushes the pin, shutting the valve.


This prevents your skimmate from flowing out the top of the reactor and into the carbon in the event it should want to overflow. Being a sealed container when the pin shuts, if there were skimmate still in the skimmers collection cup it should remain there rather than flow out onto the floor, sump, or wherever you have your waste collector situated at. If the skimmer continued to output water/skimmate at this point it would overflow at the collection cup rather than the waste collector. If your skimmer is in the sump it is better to have this overflow there then outside of the sump. If your skimmer is plumbed externally then neither option is great but the waste collector does have a backup plan there as well.


automatic power switch for protein skimmers reef octopus


Across from the ping pong ball a float switch is mounted. This float switch is connected to the yellow outlet box. When the float is in the down position, the outlet is turned on. When the float is in the up position (for example the container is full) the outlet turns off. The idea is that you plug your skimmer into the outlet and in the event your waste collector is full, or your skimmer has gone crazy and overflowed, the switch will turn the outlet off. Considering overflowing skimmers have made up the majority of my own wet floor incidents this is a pretty nice feature and if you happen to have an externally plumbed skimmer I can’t help but think either the 4” or 6” model is almost mandatory.


Octopus Waste Collector Installation:

reef octopus waste collector in action

Installation of the waste collector is pretty darn easy. You simply plug the skimmer and float switch cords into the outlet box, the outlet box into the wall, and then connect the drain from your skimmer collection cup to the input barb on the waste collector. The waste collector doesn’t come with tubing for your skimmer so unless your skimmer has a particularly long drain tube you may need to run up to the hardware store for a bit of tubing.
One last note about installation, the waste collector is supplied via gravity. Each of the collectors has a measurement for the height of the input barb, make sure the output on your skimmers collection cup is higher than the input, otherwise gravity is not going to work in your favor and your collection cup won't drain! Even on our setup on the frag tank it was pretty close, the taller one would not have worked without raising the skimmer.

UPDATE: Reef Octopus has added a delay timer to the power outlet that prevents the skimmer from turning on for a little while when power is supplied, which is a great new feature. Why you might ask? When the power goes out (you unplug it, storms, etc) the water level in your sump will go up from water draining back from the tank. If the return pump doesn't have enough time to push the water back up to the tank and restore the normal depth before the skimmer turns back on, the skimmer will be in too deep of water and likely flood. The delay gives the return pump time to get the water level back to normal before your skimmer turns back on.