Trout sales from the 146-year-old hatchery picked up three weeks ago and volunteers expect to sell out of yearling trout in the next month. 

Ballarat Fish Acclimatisation Society’s vice president Frank Gray compared the impact of the hot spell to a chlorine spill at Lake Wendouree over a decade ago which killed the hatchery’s fish in an instant.

Another time the hatchery lost fish was when the tram sheds blew up the circuit, putting the pumps out of action.

“It’s not a new thing the fish dying, but it is for some of the new members,” Mr Gray said. 

“This year wasn’t as bad as that (the chlorine spill) because that happened and it was bang, one big hit, this year it was a gradual thing, each day you’d go in and you’d be picking out a couple of hundred fish each day and burying them.

“It’s just the constant, ‘how do we stop it?’ but we just couldn’t because the water was too hot.”

A water cooling tower and filtration system will allow more trout to survive the dry.

This year the water temperatures were hotter, and the dam levels lower, than during the drought, Mr Gray said.

“If it’s a long dry summer, the water gets too hot for the trout and that’s when the disease comes in, the hot water stresses the fish out and something else kills them. 

“The cooling tower would cool the water by about 2 degrees and we should be able to have more fish come through the end in the dry and hot periods which it looks like we’re getting more and more of.”

Mr Gray said losing fish was hardest on new members. 

“We do put shade cloth over ponds and try and spray water over the top of the ponds - we try everything we can.

“The first time you spend hours and hours picking eggs and feeding trays and then virtually right at the end they die on you, it’s very gut wrenching and believe it or not you do get attached to them as well.

“In the early days when I lost fish I couldn’t sleep, you would worry when you go in ‘is there going to be more floating?’ but sometimes it’s just out of your hands.”

Ballarat Fish Hatchery will host tours of its premises when the Goulburn Trout Festival extends to Ballarat for the first time this September. 

The festival will be based on the shore of Lake Wendouree on Saturday, September 3 with tours of the hatchery every half hour from 9.30am. There will also be a release of live trout into the lake.