A fish tank in Dunedin Hospital cost more than $1000 a week to run in its first year.
However, the cash-strapped Southern District Health Board says the maintenance bill will be ''significantly less'' in the tank's second year of operation.
The tank is funded by donations to the children's ward.
It cost about $56,000 to maintain in its first year, not including the cost for electricity.
In an email, patient services director Lexie O'Shea said responsibility for maintaining the fish tank had shifted from the University of Otago's marine department to a ''local pet retailer'' for the tank's second year.
The maintenance bill included ''fully establishing the fish tank in a phased manner and introducing additional fish''.
The tank cost more than $73,000 to install, which had included fish stock and plant fauna.
''The cost for the second year is to be determined as the environment of the fish tank stabilises.
''The first year's costs [were] due to [the] needs of the fish, which included stabilisation of the whole environment of the fish tank.''
The tank is in the entrance area to the children's ward, which was opened to patients almost a year ago.