Looks to be the dreaded red bugs and are the pest troublemakers. They feed on the tissue of smooth skinned acro corals and while most dont kill coral, its their growth and reproduction rate thats an issue. They are a type of copepod bug and yes interceptor pill crushed is often a solution to knocking them down.
Do realize interceptor can and will likely kill inverts, crabs-shrimps-pods and I therefore recommend removing all inverts OR treat the coral in a separate tank without inverts and will also reduce amount of the interceptor needed.
Treat 3 times a week for 3 weeks at 25mg per 20 gallons of water. Each pill needs to be ground up with a hammer and should treat about 400 gal. Do application initially. About 8 hours later, add another. Then blow the coral GENTLY with a turkey baster and 8 hours later add another dosage. DO NOT repeat until day 7 doing another 3 treatments every 8 hours.
REMOVE CARBON AND TURN OFF ANY UV STERILIZERS AND SKIMMER UNITS.
Each 7 day periods, do a water change and siphon surfaces.
- You need the 51-100lb (23mg) plain interceptor (not plus)
- 1 pill per 100g at a minimum
- Treat every week for 3 weeks