A family of seven living just south of Adelaide is in hospital because of suspected poisoning from spores released by coral from a household aquarium which was scrubbed with a cleaning brush.

Ambulance crews were called to the house on Sunday Parade at Aldinga Beach, about 2:30am, when the residents fell ill.

They were taken to Flinders Medical Centre and remain in a stable condition.

Decontamination crews have worked at the home throughout the day.

The Country Fire Service (CFS) and police were then called to the scene, which has been cordoned off.

The CFS said it traced the problem to the aquarium because of what the family members had said and the symptoms they were displaying — mainly breathing problems.

"Those two together [we] worked out that it was the spores [from the coral]," CFS regional officer Peter Phillips said.

"It would appear that in trying to clean the coral, they've taken it out of the aquarium and scrubbed it with a brush and that's liberated the spores."

Coral experts consulted, HAZMAT teams on site

Mr Phillips said the family fell ill three to four hours after the cleaning of what he called the "readily available" coral.

Three hazardous materials removal teams are on site, wearing protective suits and breathing gear, each working in 20-minute shifts.

Marine ecologist Ivan Nagelkerken said coral products sold in aquarium shops could contain toxins which could be life threatening.

"When people start cleaning their aquaria and damaging these flower corals that's when the toxicants are released," he said.

"For example if people have a cut in their hand or if there was one case of somebody cleaning their tank with boiling water and the toxins entered the water vapour, then the effects can be really harmful."