Hey bro whq, regarding your questions above:
I know nuts about SPS....
For gonio, I do realise that it is rather sensitive to water parameters, temp, light, and wave movements. Would advise u to swop it if you wanna play safe.
For Carbon, I am ordering in the Rox 8.0 high grade carbon from Peter's bulk order. you require prob 2 tablespoon only for your tank size for a fortnight. You might want to share with me if keen. Pls PM me hor.
Otherwise, I have recently tried Pura complete. Its a mixture of carbon and phosphate remover. quite good imo.