It depends on the age of the turf. If the grass is new turf then you need to water more maybe up to 4 times a day until they are established.
If you are talking about established turf, then it will be maintenance. Grass is hungry and likes the equivalent of and inch of rain a week. How long that takes depends on how much rain you get, what kind of water pressure you have and if you are watering by hand or with a sprinkler system. If you are using a sprinkler system you can set out tuna cans out spread out on the lawn and time how long it takes for the cans to fill one inch. That will be the length of time the sprinklers will have to be on to deliver and inch for the week. You can divide the time on a couple of different days. For example if it took and 60 minutes to collect an inch in the cans you can run the sprinkler on Monday and Thurs for 30 minutes each or every other day for about 20 minutes each. If it rains hard enough to deliver at least an inch of rain you won't have to water that week.
Established lawns should be aerated, dethatched, fertilized and top dresssed twice a year.
The test for determining if you have watered enough is to look at the lawn. It should be a medim green color. If it is yellow or brown it either has disease, insects or not enough water. If you step on the grass it should spring back. If it takes a long time to spring back or stays down and the grass blades look shriveled then it is not getting enough water.
New lawns should be fed monthly.
I have dwarf St Augustine, the blades are wide and it makes long runners. It competes with weeds well and tolerates traffic and some shade. It needs to be mowed much more frequently than Emerald zoysia. It spreads relatively quickly. If it is well cared for it is pretty tolerant to pests. It likes well drained soil so make sure there are no low spots in the grass where it would puddle.
Happy gardening in Hawaii. Gardens are where people grow.