difference in spotted dollars

[EVP]

i have a shoal of assorted dollars in a 125g. i only had one spotted till recently. after a few days in the tank the new one started getting a lot of blackin his fins, which the old doesnt have. the other has light red. has anyone ever seen different spotted dollars?

school consist of:
4 black bars
3 red hooks
3 unknow
2 spotted

 

[Bogwoodbruce]

Thats a male my friend, i have 5 spotty dollars and i have 2 males they are longer and not as deep as the female and have black fin edging and a couple of large black spots near the gills. Great fish

 

[EVP]

thanks for responding bruce. Cool, so I have a male and a female. I was very happy to find him. Nobody ever has spotted and just like how I found the first one he was the only one mixed in with other dollars. This little fella is quite the pisser. He chases around even the largest red hook I have and he is pretty big.

Bruce what does your dollar school consist of?

 

[Bogwoodbruce]

Currently i believe
6x 2 species Silver dollars 6-8"
7x Red hooks 6-10"
3x Black bars 5-8"
1x Yellow hook (myleus torquatus) 6"

I have 5x 4.5" Spotty dollars in another tank. I had a lot more at one point. The most agressive one of all is the yellow hook at night he keeps all the others pinned in the corner, but he does behave.

 

[EVP]

I noticed something very interesting today. My old spotted is now showing black in his fins the same as the new one. I've had him at least 6 months and he never showed the black fins. I grew up in a house with 15 tanks and this many years later (32 years old) I still come across things in this hobby that fascinate me.