I don't think its an overkill. The beauty of the Hydra is that its modular - and there is a lot of flexibility of placement. And able to bring old equipment over when you upgrade (eg. my 3 units of Hydra26 were brought over from my previous 3ft tank)
You can get the config files here : http://www.aquaillumination.com/file/signature/ai-signature-leonTan.aip
You can also get settings of other tank size & set up from here : http://www.aquaillumination.com/signature/
Its possible to 'preview' the settings by clicking on the timing green box to bring up the intensity dialog box.
I feel that light settings should not be dependent whether a tank is 'new' or not but rather about having the right light intensity/duration vs coral type & placement.
Once the light setting is roughly about right, water condition plays a bigger role in algae growth (eg. nitrage, phosphate, dosing supplements such as liquid food, amino acids or trace elements). Let's troubleshoot this. I'll reply in your thread.