From left: Carsten Krome, managing partner and co-founder of Hatch Blue; Caitriona Kelleher, managing director of early-stage investments; and Wayne Murphy, co-founder and partner. © Hatch Blue
Land-based fish farms rely on a continuous, large-volume supply of oxygen to maintain fish health and growth. Currently, most operations obtain oxygen via trucked liquid oxygen from centralised facilities or through on-site pressure swing adsorption (PSA) or vacuum swing adsorption (VSA) generators – arrangements that are often costly and logistically complex, particularly for remote coastal locations.
Nernst addresses these challenges by generating high-purity oxygen – exceeding 99 percent purity – directly on site using ceramic membranes to separate oxygen from ambient air. According to the company, this technology gives fish farms a reliable supply at a lower cost and with higher energy efficiency, eliminating supply chain dependency and operational burdens associated with conventional methods. This technology can also be used in heavy industries, including mining, steel manufacturing and energy. These sectors similarly require large volumes of oxygen and experience comparable supply chain constraints on an industrial scale.
“For decades, the limitations of conventional on-site oxygen generation have held back productivity across industries including aquaculture, mining, metallurgy, and steelmaking,” said Nick Farandos, chief executive officer of Nernst in a press release. “Our reactor technology removes those barriers, enabling the most efficient oxygen production at any scale with near-zero maintenance and the industry's lowest operating costs.”
“Aquaculture is generating commercially attractive innovation at pace, and the sector's own fundamentals are strong,” added Carsten Krome, managing partner and co-founder at Hatch Blue. “Much of that innovation also has reach well beyond it. Nernst is a clear example: the platform that solves critical oxygen supply for fish farms has industrial-scale application across heavy industry. That is exactly what gives the Blue Revolution Fund the conviction to back it.”
Building towards commercial scale
Nernst originally joined the Hatch Blue portfolio in July 2025, receiving pre-seed funding through the Hatch Accelerator Fund II and attending Hatch Blue’s accelerator programme. The start-up later participated in an aquatech innovation studio organised jointly with Bord Iascaigh Mhara (BIM), Ireland’s seafood development agency.
“Since Nernst joined our accelerator fund, their progress has been fast and convincing," said Caitriona Kelleher, managing director of early stage investments at Hatch Blue. “The team came in with a manufacturing concept and have built it into a working system ready for its first aquaculture deployment. That kind of technical execution is impressive."
Richard Donnelly, chief executive of BIM, welcomed the announcement: “Today’s announcement shows the continued investor appetite for financing Irish aquatech, and the growing recognition that aquaculture can meet rising global demands for sustainable and nutritious food.”
The $2 million in seed capital will fund the construction of an on-farm demonstration unit to validate system performance in a real farming environment. A successful trial will pave the way for commercial customer testing and a subsequent Series A funding round to scale the technology across the aquaculture sector.
