NT Labs Marine Supercarb

NT Labs Marine Supercarb 375g UK: Phosphate Free Activated Carbon for Reef Tanks

You look along the length of the tank and the water has a faint yellow tint that was not there a few months ago.

Dissolved organics build up in every reef tank, however good the skimmer. They stain the water, cut the light reaching your corals, and carry the chemicals corals release to compete with each other. Leave them and the tank slowly dulls.

NT Labs Marine Supercarb is a 375g pack of bituminous activated carbon made for marine aquariums and completely free of phosphate. Placed in a media bag in a high flow part of the filter or sump, it removes dissolved organic molecules and colour taint and leaves the water visibly clearer.

Picture looking through the end pane and seeing the far glass as if the tank were empty, with colours looking sharper under the same lights.

I have been culturing live marine food in Wales since 2008, with 18+ years in marine aquaculture, and I am happy to advise on running carbon in a fed reef tank.

Take the yellow out of your water and let your corals have their light back.

NT Labs Marine Supercarb: What It Is

Activated carbon is one of the oldest and simplest ways to polish aquarium water. It is full of microscopic pores, and dissolved organic molecules stick to the surface of those pores as water passes through. NT Labs Marine Supercarb is a bituminous carbon, which is the coal-based type favoured for reef use because it is hard, low in dust and has a pore structure suited to the organic compounds found in tank water. NT Labs make it in the UK and state that it is completely free of phosphate, which matters because some cheaper carbons leach phosphate back into the tank and feed nuisance algae.

What Carbon Does in a Reef Tank

The first thing you notice is clarity. The yellow tint that builds up over weeks comes from dissolved organics, and it filters out the blue end of the light your corals rely on. Removing it lets more light reach the corals from the same fittings. Carbon also takes up many of the chemicals that corals, and soft corals in particular, release into the water to hold their ground against their neighbours. In a mixed reef, running carbon is one of the easiest ways to keep that chemical competition in check.

It is also useful after the event. If a coral has been stressed, something has died behind the rockwork, or you have finished a course of treatment, fresh carbon helps clear what is left in the water.

How to Use Marine Supercarb

Rinse the carbon under RO or tap water first to wash off any fine dust. Put it in a filter media bag and place it where water is pushed through it, such as a sump baffle, a canister filter basket or a media reactor. Carbon that just sits in slow water does very little. NT Labs recommend running Supercarb in the filter all the time and replacing it regularly. Follow the dosing guidance on the pack for your tank volume.

If your water is noticeably yellow, start with a smaller amount and build up over a week or two. Clearing the water quickly lets a lot more light through, and corals can be stressed by a sudden jump in light.

Why You Must Change It

All carbon fills up. Once the pores are saturated it stops working, and as NT Labs point out, it can then release what it has collected back into the water. In a heavily stocked reef that happens sooner than you might expect. Many keepers change their carbon about every four weeks. Putting the date on a piece of tape on the sump is the simplest way to remember.

Take carbon out before using any medication or liquid treatment, because it will remove that too, and put fresh carbon in when the treatment has finished.

Carbon and Live Food

A question I am asked a lot is whether carbon strips out live food. It does not. Carbon takes up dissolved organic molecules, not living plankton, so you can carry on dosing live phytoplankton and adding live copepods with carbon running. The two actually work well together. Feeding a reef properly adds organics to the water, and carbon helps keep the water clear while you do it.

The pack does not include a media bag. The D-D media socks we stock are a good fit for carbon and come as a pack of two, so you always have a clean one ready for the next change.

NT Labs Marine Supercarb FAQ

Is it reef safe?

Yes. It is made for marine aquariums and is free of phosphate.

Do I need to rinse it?

Yes. A quick rinse removes loose dust that would otherwise cloud the water for a short time.

How often should I change it?

Follow the pack guidance. As a rule of thumb, most keepers change carbon about every four weeks, and sooner in a heavily stocked tank.

Can I run it all the time?

Yes. NT Labs recommend keeping it in the filter all the time, as long as it is replaced regularly.

Will it remove my phytoplankton or copepods?

No. Carbon takes up dissolved organics, not live plankton.

Does it come with a bag?

No. You will need a filter media bag or a reactor.

If you are not sure how much carbon to run on your system, get in touch. Darren responds personally.