We started off September by sitting in a classroom, Lulu and I. The teacher, Lars turned to us and asked, ‘Why are you doing this course?’

Lu started first. She said, ‘Because I’ve been diving for a while and, like you said, I’d like to give back to the corals.’

Lars nodded pleasantly and turned to me. ‘And you?’

I gulped. Where do I begin?

I’ve wanted to learn about re-building coral reefs since before we left Wales. It was one of the things I’d always hoped we could do in the Caribbean. Personally, I like it because it’s a bit of a mix between IVF, which I did as a scientist, and horticulture. Coral being animals, but behaving much like plants in the way they grow in one place. I like growing stuff.

The science is interesting. People are at the beginning – learning how to grow corals and re-plant them back into coral reefs. At this point, no one knows whether these efforts will work on a scale that can begin to make a difference for the global plight of the coral reef. I imagine too, like the majority of all things biological, the more you learn, the more you discover things which are mysterious. Almost unknowable.

That’s what I wanted to say. Instead, I felt Lu’s nail dig into my leg. She piped up, ‘She’s wanted to do this like, forever.’

I nodded in relief. ‘Forever.’

We’re doing the PADI Reef Renewal speciality certification. Set up by the independent organisation on Bonaire called Reef Renewal. Taught by Dive Buddy dive centre, one of the largest dive operators on the island. Buddy Dive has a number of large day boats which would be out, taking people diving. The majority of these boats are sitting on their mooring buoys, outside the dive centre. I’m not complaining. All I keep hearing about recently is how busy Bonaire usually is.

Normally too, there would be a bustle of people doing this course. How many today? Me and Lu. For two students, we had four teachers overall. Lars teaching and three watching and assisting.

In the classroom, we learned the overview of the coral-growing process. Because this was a dive speciality, it was practical. Lars had a replica coral-tree in the classroom in no time. He had dried prices of staghorn coral tied with monofilament line and hanging from fibreglass rods. They looked like Christmas decorations.

Our job, with crimpers and bits of metal, was to learn how to hang the coral. And how to clean the tree. We were to learn to scrub the resource-competing algae off, much like we scrub the underside of Quest. They even use the same high-tech tools. Scrubbing brush and scourer.

With no time to surmise or reflect, we suited up mid-afternoon and went to do our first reef renewal dive. I looked at Lu. She smiled back at me. The best thing about the whole thing. She was here.

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