The sheds are lined with trough after trough of black worms, splitting and growing and earning.
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The former trout farmer has wormed his way into an emerging market during the past two decades to now own and operate Australian Black Worms with his wife Beth.
“The worms are very, very high protein food for tropical fish,” Mr Davidson said.
But he only has one client who is patient enough to bait the tiny worms — it takes about 120 worms to make up 1g — onto a hook.
Most of the worms become food for tropical fish in private homes.
Platypuses at Sydney Aquarium are also treated to a feed of the worms each week.
Mr Davidson said they were black worms known as Lumbriculus variegatus not tubifex worms.
The market seems to have an appetite for the worms so it’s lucky they multiply so quickly.
One 6-metre long by 50 centimetre wide and 50 centimetre deep trough can create 6kg of worms every six weeks.
“They are absolutely amazing,” Mr Davidson said.
But it’s taken a long time to perfect the growing process.
Mr Davidson gave away a 21-year career as an army mechanic to take over Golden Hills Trout Farm 25 years ago.
At the time he didn’t know the true value of the little black worms breeding in the ponds.
When a bloke from Everton approached him to buy some of the black worms that grew naturally in the trout ponds, he began to learn about a whole new industry.
He realised he could get $17/kg for the worms, much more than $6/kg for trout he was returning.
“I decided I’d better start growing them (worms),” he said.
“I started on a commercial basis 18 years ago,” he said. “And 10 years ago we closed the trout farm.”
Mr Davidson has specially designed the troughs and the filtration system where the worms breed through a process of regeneration of separated segments.
The worms are “harvested” by scooping them out of the troughs.
Mr Davidson takes as many of the worms as he can but he said it was remarkable the few left hiding under the gravel could continue to regenerate, and in six weeks fill the trough.
The worms are fed twice a week on a “special formula” and are highly light and temperature sensitive.
They prefer the dark and warm water.
“Water here is 4 degrees in winter,” he said, before explaining this slowed their growth.
“It was 29 degrees on Black Saturday, way too hot, we lost a lot.”
Mr Davidson said they sold an average of 160kg to 180kg of live worms each week.
“We can produce more than that,” he said. “But they don’t freeze well.”
He said the worms just defrosted as “mush”.
So Mr Davidson went looking for an alternative, and found the answer in freeze-drying.
After sending a sample to Melbourne to be trialled and buying a second-hand freeze-dryer for $30,000 six years ago, Mr Davidson had plenty to learn.
“It’s taken me ages to really master,” he said.
“But now what doesn’t sell in a week is frozen and dried.”
The 3kg blocks of frozen worms are loaded into the freeze-dryer, which can take about 110kg.
The freeze-drying takes about 12 days with the machine he has. The one he’s looking at now could freeze-dry 80kg in 24 hours.
The blocks are sent out into the air again to take in some moisture to make them easier to process.
Processing involves cutting the blocks into small cubes or creating a desiccated product.
Mr Davidson said the dried product was still in the developmental stage and was predominantly sold to specialised aquarium shops in every state capital as well as a website.
“There are good markets in Australia,” he said.
England is also buying the product in bulk.
“We are about to start sending it to the US,” he said.
“For some unknown reason it’s good, really good.
“It’s the highest natural protein for fish.”
Mr Davidson initially thought the product would need an “attraction” like other processed pet food but has found it’s not necessary.
“This is 100 per cent natural and the fish love it,” he said.