I should never have agreed to buy Sasha fish for her tenth birthday. But it seemed like such a modest request. It’s not like you’re going to come home one day to find they’ve escaped or starved to death — like certain rodents I can think of. I was also lulled into a false sense of security by Sasha’s promise that she would look after them herself. I wouldn’t have to lift a finger.

It wasn’t until we were in the pet shop that I discovered she had something more exotic in mind than a couple of goldfish. She wanted tropical fish. That meant spending £100 on a 50-litre tank, complete with built-in filter and heating element. We were then told by the pet-shop owner that he wouldn’t be able to sell us any fish until we could prove that the nitrate levels in our tank had fallen below a certain level. Luckily, all the products we’d need to ‘prepare’ the water just happened to be on sale in his shop. Handy, that.

Fast-forward two weeks, by which time I’d spent the best part of a Saturday afternoon assembling the fish tank. Sasha’s contribution was to watch me like a prison warder and scream if I deviated from the instructions by one jot. We went back to the shop with a water sample and — heaven be praised — were given permission to buy some fish. ‘How about some zebrafish?’ the man suggested. ‘They fall into the category of “hard to kill”.’

‘Sounds good to me,’ I said.

We returned to Acton with 12 zebrafish and began the process of introducing them to their new home. The most tedious part was standing beside my daughter as she painstakingly thought up names for all 12 of them.

By 6 p.m., I thought my labours were at an end, but no. Sasha came bursting into the kitchen in a state of hysteria, complaining that the filter wasn’t working properly. I tramped back up the stairs and discovered she was right. The filter was positioned behind a couple of panes of plastic, creating a special chamber at the back of the tank and for some reason it had managed to pump most of the water out of this chamber and was now making a continuous farting noise as it blew air into the rest of the tank. My solution was to push the filter deeper into the chamber until it was once again submerged.

‘Are you sure that’ll be all right, Dad?’ asked Sasha. ‘It’s not going to hurt the fish?’

‘It’s fine,’ I said. ‘They’re “hard to kill”, remember?’

All was well until it was time for bed. At Sasha’s insistence I went with her to her room to check on the fish, only to find that all hell had broken loose. My ‘ingenious’ solution hadn’t worked. The filter had emptied its chamber of the remaining water and was sending a jet of air into the main tank with such force that it had created a kind of fish Jacuzzi. Two of the fish had been propelled out of the tank and now lay dead on the carpet.

‘Dad!’ said Sasha. ‘You’ve killed Zip and Zap!’

I plunged my hand into the chamber to wrench out the filter, but it had somehow got wedged beneath the heating element. So I removed that and placed it on the carpet next to Zip and Zap, at which point Sasha, who was hopping from foot to foot with anxiety, trod on it. Cue meltdown. But before I could tend to her foot, I still had to deal with the rogue filter and in my haste I managed to break one of the panes of plastic. As the water levels equalised, the remaining ten zebrafish poured into the broken chamber and disappeared into the inner workings of the tank. It was fishmageddon.

After Sasha had been sedated and removed from the room by Caroline, I set about repairing the tank. That involved emptying 50 per cent of the water so I could stick the broken pane back together. By the time I’d completed the job and refilled the tank, only two fish survived.

Several weeks have passed, but I don’t dare reinsert the filter in case it malfunctions again. The upshot is that the water has turned dark green and the nitrate level must be quite high because the two survivors are on their last legs. Less like Zip and Zap, more like Drift and Float. So much for low-maintenance pets. It’s almost enough to make me want another hamster.