From microalgae to macro grouper

During a long and colourful career in aquaculture, Knuckey – who is MD of The Company One – has seen some extraordinary sights. From growing microalgae in a neon pink Western Australian salt lake for the beta carotene sector, to rearing larval oysters for CSIRO in Hobart, to leading one of Australia’s top tropical finfish farms in Cairns, he’s encountered a wide selection of species and scales. 

“When we first started off, we had giant grouper broodstock of 130 kg, because we thought we'd need to go that big. But they were difficult to work with. So we ended up donating them to public aquariums. One of them went to Melbourne and promptly ate two lemon sharks,” he recalls. 

Knuckey’s been with his current company since 1999, at which time it was a government-run research hatchery. Since then it’s gone through a number of incarnations and species but – following its acquisition by a Hong Kong-based investor in 2017 – it’s now a commercial entity trading as The Company One.

One thing that hasn’t changed is the company’s focus – trying to capitalise on the lucrative live fish trade to Asia, in the face of declining wild catches of species such as grouper and coral trout. 

“When it [the acquisition] happened I couldn't understand what was in it for them, because we were playing catch-up with grouper research compared to Taiwan and the rest of Southeast Asia. But, as it turned out, they'd been searching for quite a long time to find high quality and disease-free grouper stock. So that's what our strength was compared to anywhere else in the region. And, fortunately, they saw the value in what we did,” Knuckey reflects. 

“Since they've been able to get our fingerlings it’s solved a lot of their [disease] issues. So it's been a really good linkage,” he adds.

As MD, Knuckey oversees the production of around 1 million giant grouper, blue-speckled grouper, coral trout and footballer trout (Plectropomus laevis) every year, but with the capacity to double this figure. 

“Our strengths lie within our ability to bring on new species and to understand the breeding processes. You don't often get that opportunity to take your research through to commercialisation, so it’s been pretty exciting and pretty fun,” he reflects. 

It’s clearly a species group, and a role, that he’s very content with, but it still remains a fringe genus for farming outwith Asia – and Knuckey does admit that it’s not easy, even after 25 years. 

While he no longer deals with 130 kg behemoths – the company doesn’t keep broodstock past 60 kg – the other end of the life cycle is still problematic. As he explains, first feeding is one of the most challenging times, not least as the hatchery needs to dramatically ramp up copepod production shortly before they expect their broodstock to spawn. And the timing is made all the more tricky to judge, as the company prefers to use photothermal and lunar control – not hormones – to induce spawning on the farm. 

However, they have gradually fine-tuned both processes, meaning that the newly hatched grouper should have a fresh, live copepod banquet awaiting them by the time they are ready for first feeding.  

According to Knuckey, while other hatcheries rely solely on rotifers for first feeding, a steady supply of copepods in the first few days has helped his team improve survival rates and reduce deformities. 

“The most important part is at first feeding. So we just need to add copepods to the diet so that on day three when the larvae are ready to feed, the copepod nauplii are there. The bulk of their diet still remains enriched rotifers. But the copepods are what gets them over that line and make all the difference,” he emphasises. 

Another issue with the species is nodavirus.

“It's okay in a RAS, but in a growout ponds, it's hard to manage nodavirus and unfortunately the groupers tend to be susceptible to nodavirus through their whole life cycle rather than just early on like you see in many other species such as barramundi,” Knuckey reflects. 

However, they have since tried working with blue speckled grouper, which appears to be less susceptible to the virus than the giants. 

“That’s been really interesting. It's a new species for us. Its growth rate is comparable early on to the giant. But our latest research in collaboration with James Cook University has shown that it catches nodavirus but it doesn't affect it,” Knuckey explains. 

The majority of farmed grouper are sold live for the Asian market – including the Asian diaspora – where they fetch premium prices, but The Company One focuses on the hatchery side of the production cycle, selling around  60 percent of their fingerlings for ongrowing by two farms in Australia and the remaining 40 percent to its sister companies in Taiwan and Hong Kong. 

Despite this, Knuckey admits that – one day – he’d be delighted to be able to grow grouper from egg-to-plate on this own farm, thereby completing the process and allowing him to fully capitalise on the company’s knowledge.

“Early on, perhaps we would have struggled, but now we know so much more and we know that we could do a really good job if we had a farm of our own,” he points out.

However, he concedes that raising the necessary capital wouldn’t be the only issue. 

“It's actually very hard to find suitable farms and to get a new aquaculture permit in Queensland is very difficult,” Knuckey observes. 

Recent breakthroughs

As a result, the company is currently focusing on ways to break into the market in mainland China instead. And, as there’s a strong demand for red-coloured fish there – as red symbolises luck, joy and prosperity – they are keen to produce more coral trout. 

Looking further ahead, while Knuckey might suspect that developing a commercial RAS operation in Australia is a bit of a pipedream, in the medium-term he’s more confident about the potential offered by working with partners in mainland China to establish satellite hatcheries.

They’re also considering partnering with European clients, and have already done some work with Oceanloop – who have a pilot shrimp and grouper farm in Germany as well as plans to open a much bigger facility in Gran Canaria. 

“To be able to shift the fingerlings that far around the world without mortality was really a good result. That's been quite interesting and I think there's a good market there,” Knuckey reflects. “And if they go to that next level it would make sense to build a hatchery within Europe somewhere.”

“It’s been really, really encouraging to see how well they're doing in a system and a country that you wouldn't imagine growing grouper,” he adds. 

It only helps to confirm Knuckey’s belief that grouper are a very strong contender for growing in RAS – wherever there’s a market. 

“They're so tolerant to high densities and quite fluctuating water quality, because they're an estuarine species. They're used to living in fairly dynamic water bodies, fluctuating in nutrient load and salinity and DO [dissolved oxygen] levels. We've had semi-RAS operations with stocking densities of 100 to 150 kilos a cubic metre without stress being shown by the fish. And because they're not really active swimmers, they just hold a position in the water column, they don't waste a lot of energy and don’t need the sort of space that you might see with more pelagic species,” he concludes.