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Marine Spec
In stock
Black frag plugs for reefers who find bright white plugs distracting.
Best forSPS frags and a low profile look in the rockwork
Bright white plugs can pull the eye away from your aquascape.
These are black, so they blend into most aquascapes instead. You get 2 shapes: a 25mm round top and a 27mm square top, both 20mm tall with the stem attached.
Each plug has a textured top with a small divot in the middle.
That gives glue or putty something to hold on to, and it is why we recommend them for SPS frags. The stem detaches fully, so you decide whether a frag sits tall or flat.
Some 3D printed plugs float or hover when they go in the water.
We designed these with enough density to sink, so a plug stays where you set it while you line up a row of frags. Ours settle on the bottom, which makes placing a full pack of frags simpler.
The plugs are compatible with the FragDoc, a small dock that glues to your rock and holds a plug.
Lift a frag out when you want to swap or rotate it. The FragDoc is sold separately, and you can buy both in packs.
You get 2 shapes. The round plug is 25mm across the top and the square plug is 27mm across the top. Both are 20mm tall with the stem on.
| Shape | Top | Height with stem |
|---|---|---|
| Round | 25mm | 20mm |
| Square | 27mm | 20mm |
No. The stem is fully detachable, so there is no trimming and no bone cutters. Take it off and the frag sits flat, or leave it on and the frag sits on a stem. You choose for each one.
Yes. Some 3D printed plugs float or hover. Ours are designed with enough density to sink, so a plug stays where you put it while you line up your frags.
They do. The plugs are compatible with the FragDoc frag plug holder, which glues to your rockwork. The FragDoc is sold separately and appears in some of the photos to show how the pair fits.
That is a call about looks. Black blends into most aquascapes, where bright white plugs stand out. The textured top and central divot give glue or putty something to grip, which is why we say they suit SPS frags.
Looking for somewhere to hold your frags? See the frag plugs and docks range, or browse frag racks. New to all this? Read what a frag rack is.
Packs come in 5, 10 or 20. Pick by how many frags you want to mount in one go.
Not sure it suits your tank? Message Harry on WhatsApp. He runs Marine Spec from his home in Suffolk.
Related guide What is a frag rack, and how do you use one?That is up to you. The stem is fully detachable, so you can leave it on for a frag that sits up on a stem or remove it for a frag that sits flat. Either way you do not need bone cutters to trim it.
Yes. Some 3D printed plugs float or hover, but ours are designed with enough density to sink reliably. That matters when you are lining up a row of frags and need each plug to stay exactly where you put it, rather than drifting about the tank.
Yes. They are compatible with our FragDoc, which is 18.5mm tall and 15.5mm across, and it glues to your rockwork so a frag can be lifted out later. The FragDoc is sold separately, and it only appears in some photos to show how the system goes together.
The only difference is the top. Round is 25mm across and square is 27mm across, and both are 20mm tall with the stem on. Both have the textured top and central divot, so choose the shape you prefer for the frag.
Packs are 5, 10 or 20. Count the frags you plan to mount at once and pick the pack that covers them. If you frag often, the 20 pack gives you room to keep going. The pack size changes the price, not the plug itself.
Choose options3D printed
Mounting frags on rockwork so they can be swapped
3D printed
Acclimating and growing on coral frags on the glass
Choose options3D printed
Settling new corals on the tank floor
