Are Grubblies better than mealworms?

Black soldier fly larvae treats like Grubblies outperform dried mealworms on calcium — the single most important nutrient for laying hens — containing roughly 85x more calcium per gram than mealworms do.

The reason that calcium advantage actually matters comes down to ratio: black soldier fly larvae contain both calcium and phosphorus at a favorable balance, which means the calcium gets absorbed and used by the hen's body rather than passing through. Dried mealworms are high in phosphorus but comparatively low in calcium, which can actually interfere with calcium absorption. For keepers tracking eggshell thickness or supporting hens through molt, that difference shows up in practice.

• Black soldier fly larvae contain approximately 2–5% calcium per gram versus roughly 0.05% in dried mealworms.
• BSFL protein content runs 36–42%, supporting feather regrowth during molt (feathers are ~90% protein).
• BSFL contain lauric acid, a fatty acid with antimicrobial properties not present in dried mealworms.
• Recommended treat quantity for laying hens: 5–10% of daily diet, roughly 0.5–1 oz per hen per day.