WHEN it first opened its doors, it is hard to imagine that Bolton's very own aquarium would be breaking world records.

Hidden away in the basement of the town's main library and museum, Bolton Aquarium is a gem which has changed so little but so much in its 75 year history.

Today it is home to more than 70 varieties of fish from all around the world with more than 100,000 visitors coming to peer into the tanks, a world away from when the aquarium first opened its doors to the public on January 27, 1941.

Back then, in the midst of the Second World War, the attraction was only able to collect British fish from local sources, including salmon, pike and trout.

It was reported at the time of opening that there was a stream of visitors eager to get inside the room which was decorated in black tiles with brass railings to keep them away from the tanks.

Pete Liptrot, collections access officer, has been at at the aquarium since 1993.

He explains: "We don't know why there's an aquarium in Bolton, it is not recorded in the archives and if anyone does know we would like to hear from them.

"You have to assume some councillor thought that it would be good to have an aquarium, maybe after visiting Europe and seeing something similar in Berlin or the like.

"There was a time during the Victorian era where there were aquariums in towns like Brighton which were on the pier and open over the summer. When the season ended they would check the animals back into the sea and they would swim off."

The aquarium grew in popularity over the decade, attracting more than 10,000 visitors a month keen to glimpse the fish which were being caught by fishermen from local rivers and ponds.

The 1960s increase in international trade meant new species could be brought to Bolton from increasingly exotic locations, including the South American Neon Tetra and Pygmy Chinese Squirrels, but sadly many did not last long in captivity.

The aquarium went on to diversify in the 1970s, introducing a reptile collection which included snakes, bearded dragons and even tree frogs.

Despite its popularity the collection was phased out in the mid-2000s when the service decided to focus on fish and not to compete with major reptile and amphibian collections in Manchester.

"Fish is what we are really well know for. We've bred so many first time in captivity, with firsts in Britain, Europe and the world," Pete adds.

"We are a fresh water aquarium and keep fresh water animals. Bolton tap water comes from a nice clean reservoir so we are actually able to keep a lot of fish in very good conditions.

"We don't keep cold water or cool water fish anymore. This building is heated to a very warm temperature and some fish don't do well in these sorts of temperatures.

"Tropical fish face much more threat in the wild. Of all the water in the land 0.1 percent is fresh water and half of that is bound up in ice caps and glaciers but 40 percent of the world's fish species is fresh water. Therefore fresh water fish are more vulnerable."

The aquarium was given a facelift, removing the railings and adding more tanks, in the 1970s, then a decade later was properly licensed as a zoo for the first time.

The collection kept on growing, including an the most electric fish in the world; a Lungfish eel, originally from the Amazon, which can give a shock of up to 300 to 500 volts.

British fish were kept up to the 1990s before moving on to totally focus on tropical fish which was boosted by the arrival of several rare and threatened species from Madagascar, Lake Victoria in Africa and Mexico.

Then in 2006 there was a world first when it bred one of the smallest tropical freshwater fish in captivity, the Pygmy glass Danios — the tiniest fish in the world — as well as the Celestial Pearl Danio and the Rasbora dandia.

Despite its small size, the success of the aquarium has attracted a international reputation for its excellent knowledge of fish care, being contacted by institutions from all over the world for help with husbandry and breeding of freshwater fish.

Some of the Danionell bred at the aquarium have recently travelled to Berlin University where their breeding and growth will be further studied, and there will soon be visitors being welcomed from the US for the same reason.

Modern technology has also helped open doors as the experts at the aquarium get to share experience with their counterparts around the world via social media.

Pete added: "Hopefully the care for the animals has improved massively over the years because we've learnt so much and there is so much more knowledge available to us.

"Historically the information we needed was hard to get hold of. Now we can use Twitter and Facebook and get all sorts of things. You can video a fish doing something in a tank and send it to someone on the other side of the world to ask if their fish is doing it too, and they can tell you how theirs is behaving and you can jigsaw together all this knowledge."

"We hope to go on from here, 75 years would just be the start of it even though it has been a long time already."