Fiji Cube Magnetic Frag Rack Review: A Secure Home for New Coral Frags

Introduction

Coral frags accumulate quickly in a reef tank. You might be trimming colonies that have grown into each other, picking up pieces at a local fish store or a frag swap, or waiting on an order from an online vendor. Either way, there is usually a stretch of time before you decide where each piece will be glued down permanently, and that stretch can run from a few days to a few weeks.

Leaving frags loose on the rockwork or in the sand bed is a reliable way to damage them. A frag sitting on the sand can be knocked over and buried, and one balanced on rock can be nudged aside by a snail or a fish and land on a neighbouring coral. The Fiji Cube magnetic frag rack exists to close that gap. It gives frags a dedicated, secure position on the aquarium glass while you work out their final placement.

Who this product is for

This rack suits reef keepers who hold frags regularly rather than once in a while. Anyone who brings home frags from swaps, fellow hobbyists, or online vendors will recognise the problem it solves: a safe holding area that keeps plugs upright, exposed to light and flow, and away from the sand bed.

Fiji Cube offers the rack in three sizes: an 8 plug version, a 16 plug version, and a 32 plug version. Lengths run from 8.25 inches up to 11.35 inches, so the smallest option fits neatly on a narrow side panel while the largest handles a full batch of new frags.

All three sizes are built around the same design, so the choice comes down to how many frags you typically need to hold at once and how much glass space you are willing to give up.

Main strengths

The standout feature is the plug locking system. Between the upper and lower plates of the rack, a softer white material sits in each hole and provides five small nubs. Those nubs press against the stem of the frag plug, adding resistance so plugs are not easily bumped or jostled. This matters most with thinner plug stems that sit loosely in a standard half inch hole, and it also helps in tanks where snails, fish, or strong flow have a habit of rearranging frags.

Mounting is handled by N52 triple coated neodymium magnets, sealed in water tight acrylic, and the rack holds firmly on panels up to half an inch thick. The platform itself is only three eighths of an inch thick, which keeps the rack visually light in the tank.

Fiji Cube also made the racks modular. The layers are held together with a removable plastic rivet system, so the rack can be taken apart when it needs cleaning. That is a thoughtful detail for anyone who has watched algae and debris collect in the seams of equipment over a few months of use.

The finish is worth noting too. Black cast acrylic on top blends into a tank with a black background, while a transparent blue lower section reduces the overall silhouette and the rounded corners keep the shape clean. If you photograph frags on fluorescent acrylic rods, the solid black surface makes a tidy backdrop.

Things to consider before buying

The racks are designed for plugs with a stem diameter of half an inch or smaller, and the holes are spaced half an inch apart. If your frag plugs use thicker stems, they will not seat properly. Similarly, the magnet mount is rated for panels up to half an inch thick, so very thick glass or acrylic falls outside its range.

Because the rack is assembled in layers, debris and algae can work their way into the space between the plates over time, including around the locking nubs. The modular build makes that manageable, but it does mean occasional disassembly is part of owning one.

Before any new coral goes onto a rack, it is worth running a dip treatment to reduce the chance of unwanted coral pests travelling into the tank. Starting with a suitable dip solution is a simple step that protects both the new frag and everything already growing in your system.

Buying advice

Pick the size based on how many frags you realistically hold at any one time. An 8 plug rack is enough for occasional additions and keeps a low profile on the glass, while the 16 plug version is a sensible middle ground for most mixed reefs. The 32 plug option makes more sense for keepers who regularly buy in bulk or run a dedicated grow-out area.

Measure the panel you plan to mount it on before ordering. Confirm the glass or acrylic thickness is within the half inch limit, and check that the rack length fits the section of glass you have in mind without crowding nearby equipment. Also check the stems on the plugs you use most often, since half an inch is the ceiling for the locking holes.

Finally, treat the rack as part of your maintenance routine rather than a permanent fixture. The ability to take it apart means it can be rinsed and reassembled periodically, which keeps the locking nubs effective and the acrylic looking clear.

Conclusion

The Fiji Cube magnetic frag rack addresses a genuine problem in reef keeping: what to do with frags before they are glued in place. The locking nub system, the N52 magnet mount, and the modular, cleanable construction all point to a product designed by people who have lost a frag to a snail. For reef keepers who hold frags often and want them secure, tidy, and easy to see, this rack is a well-considered option in any of its three sizes.