Been using this style for many years.
Hard to lock with water in it
They are now my go-to for my chicken supplies. Easy to order, fast to ship.
This daily calcium supplement for birds supports breeding birds and their young with essential calcium. It contains vitamin D3 to maximize calcium absorption in the gut. Supports shell formation and the normal development of bones in young birds. Regular use in all seed-eating birds will ensure adequate calcium for strong bones, muscle formation and general well being. Can also be used as an emergency oral calcium supplement for egg bound or critically deficient birds.
Size: 50, 100, 250, 500, 1000 ML
Add 5mL per 250mL of drinking water. Use as the sole source of water and prepare fresh solution daily (1tsp per cup of drinking water.)
Pour 5mL over 1 cup soaked seed.
0.2mL per 100g body weight (Add 4 drops per 3½ oz body weight.)