There are a number of dystopian references in Weaverfish, hinting at the existence of a larger back story than what is directly depicted on screen. The fictional town in which the film is set is called Huxley Wells, combining the surnames of science fiction authors Aldous Huxley and HG Wells. The fictional location, Fountainhead Creek, is also named after Ayn Rand's "The Fountainhead". In Weaverfish, the company supplying the barrels of biological solvents is named Aquatopia.

The dread-locked wig, worn by John Doughty for the role of Mike Eagle, was previously worn by Faye Tozer in the Steps music video of "Tragedy".

Before filming, Lucy-Jane Quinlan was told that her character Charlotte was pregnant with Matt's baby. None of the other actors were informed of this, nor was it ever referred to in the film.

Shane O'Meara's feature film debut.

There are a number of crew cameos in the film. The gas-masked figures were regularly played by members of the crew, including Mark Maltby, Thomas Shawcroft, Ciaran Maginn, Charles Shawcroft and Trudy Pye. The gas-masked figure that strikes down Shannon in the long-grass was played by Director Harrison Wall.

The entire cast and production crew spent 16 days living in the household of Cinematographer and Hamble local Thomas Shawcroft during the making of Weaverfish.

Weaverfish was written to be shot in the location of Hamble-le-rice in Southampton, UK.

The film was made on a budget of £10K. This was self-funded by Director Harrison Wall and Producer Mark Maltby.

Weaverfish was shot in 16 days. Most of the cast and crew were working full time jobs and took 2 weeks holiday to attend the shoot.

The wide shots of the perimeter fence were created in visual effects. However, the close ups, in which the characters interact with the fence, were filmed using a budget piece of mesh fence from a garden center. This involved having two crew members stood up to their waists in water holding the fence from off screen.