The crew performed CPR on Elliott until a St John ambulance crew arrived, however their attempts to resuscitate him proved unsuccessful.
Mr Bennetto said their crew was in the middle of training when they got the call.
"So when they came back they were a bit quiet on it," Mr Bennetto said. "There's a few of them who have got children of their own so that's always a bit tough."
The house was cordoned off overnight while police conducted a scene examination.
Elliott's death has been referred to the coroner.
A neighbour, who didn't want to be named, said she only the knew the couple to say to hello to as they had not lived in the house for long.
Plunket didn't want to comment on the incident, however its website offers tips and advice for parents when bathing their children.
It advised that drowning can happen easily and quietly.
"If a parent is home alone with their child or children, it can be helpful to plan ahead so they're not distracted. You might turn off anything cooking and take a cordless telephone into the bathroom. Watch your toddler while the water is running so that they don't get in without you, watch them the whole time they're in the water. If it's a bath, empty the water as soon as it's finished.
"Bathing can be great fun for your toddler, but many don't like bathing right away. There are many ways to get your toddler enjoying their bath time, but the most important thing is to keep bathing safe."
TOP BATHING TIPS:
(source: Plunket NZ)
* Offer them anything that sinks or floats: empty drink bottles, plastic cups or jugs, boats, and more.
* Try a gentle, one-step-at-a-time approach.
* Stand your toddler in an empty bath or turned-off shower and sponge them with warm water.
* Each wash time, gradually introduce the bath or shower water.
* Start your toddler in the bath or shower with company: an adult, or brother or sister.
* Don't leave your child with anyone under the age of 14.
* Keep watch the entire time.