The adults, first hit by the toxins, spent one week in hospital. Katie's three girls, who were asleep, were discharged the day after.

Katie added: "We had gone on holiday and our fish had died, so we decided to get rid of the tank. We completely emptied the tank and started scrubbing it. When you scrub it, it lets off toxins.

"The house had to be completely cordoned off by the police and fire brigade.