i can only speak from my single experience. i think 2/3s the largest fish is fine for the smaller fish so long as the shoal is large. they hit the 6-8inch mark quickly then slow down. your others should be fine catching up. i introed smaller fish to the shoal before. 2 3inch when the largest was 6inches, shoal of 5. one of them dissapeared. smaller or weakest fish usually gets beat up pretty bad in the beginning. if you see bare meat, should seperate. i've seen the skin broken 3 times, 2wice those fish died, the one that didnt was cos it was seperated, then reintroduced after beefcake program and didn't have any issues.
larger they get, slower they'll swim around. so while i dont think they need a 10fter, wouldnt be comfortable fitting a shoal in less cos at feeding time, they go full boost. I could see one cracking glass in a smaller/thinner tank.
i've got 7 in a shoal. 6-8inchers. tankmates that are eigher significantly tougher than them, and or different shape/color than them, and or larger than them do better.
i agree, great fish to watch. they don't stop. i bet when a dorado dies of old age, it just stops in mid-stroke, it's heart just explodes.
larger they get, slower they'll swim around. so while i dont think they need a 10fter, wouldnt be comfortable fitting a shoal in less cos at feeding time, they go full boost. I could see one cracking glass in a smaller/thinner tank.
i've got 7 in a shoal. 6-8inchers. tankmates that are eigher significantly tougher than them, and or different shape/color than them, and or larger than them do better.
i agree, great fish to watch. they don't stop. i bet when a dorado dies of old age, it just stops in mid-stroke, it's heart just explodes.

