Mr Clay has run the business via a website for about seven years and the retail premises is a progression based on increasing demand.
"I've been using fountain pens since I was at school," Mr Clay said.
"They are much nicer to write with than ballpoint pens and a lot of people enjoy writing with them.
"I often have people phone and say they have a favourite pen but they can't find a refill for it. If they bring it into the shop, I can generally get a refill for them."
Mr Clay says a lot of younger people are now using fountain pens.
"If you have a ballpoint pen you can have blue or black or blue/black but with a fountain pen you can write with 'your' colour or change the colour of the ink depending on how you feel that day.
"It's like a retro throwback thing but it doesn't have to look old-fashioned. People are writing letters and taking time to think about what they're writing. It's a little more meaningful [than electronic communication]."
Mrs Clay compares the experience in the store with shoe shopping.
"We have women come into the shop and it's like buying new shoes," she said.
"They are looking at all the ink colours and flipping through the catalogue to find the colour they like. Very few people own just one fountain pen; it's a pen enthusiast type of thing. It's cool."
The shop is open Monday to Friday 8.30am to 5.30pm, Saturday 9am to 2pm and Sunday by appointment.