First the good bits: the dive shop attached to the hotel, Thalassa, is excellent and perfectly located to dive the wonders of the Bunaken marine reserve. And the spa does good massages.
But you don't have to stay at Santika to use Thalassa, and we recommend that you don't. The property should have everything going for it: good buildings, nice pool. But the service was truly awful. There was no-one around who could help with any questions, either because of lack of English (or any other European language) or because people simply didn't know the answer. The concierge desk was never manned (it transpired that the concierges had other jobs as drivers), and virtually none of the activities described on the hotel's site appeared to exist.
We were in the "Cottages", supposedly the best rooms. They were large enough and adequately appointed but by no means luxurious. Dim lighting made them rather dingy, and the first signs of poor maintenance were definitely there (plumbing not working quite right, door locks not quite fitting).
Food was very poor, buffets lacking in variety and freshness, a la carte service taking up to 90 minutes at times. On one night, they simply closed down the whole of the main restaurant because of a corporate event, leaving 50 guests to be served by around 3 staff in the "Big Tree Cafe".
The atmosphere was described by several people as "like a morgue". Two families, both return visitors, said that the place had deteriorated since the previous year.
We voted with our feet and found alternative accommodation after a week.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC