Great news!
Now that you have your fish on silversides, you can begin mixing in other foods such as raw table shrimp, SW fish flesh (tuna, salmon, cod, snapper, etc.), lobster (you can often find petite tails for $5), scallops, squid, etc. Be sure to keep the chunk size manageable (a bit smaller is better than a bit larger).
Also, you'll want to back off on your feedings a bit. We feed our Scorpaeniformes 3x a week (M-W-F). Feed until you see a nice little "belly bulge", but don't feed the fish to satiation. This will help prevent hepatic lipidosis. Lions are binge/fast preds preferring to eat and digest before hunting again, and this matches their natural feeding habits more closely. However, lions will eat pretty much anytime you offer them food, so they always SEEM hungry.
Since your lion can see you at your desk, it may even learn to spit water at you to see if you'll feed it...they're worse than little dogs when it comes to begging.