Adding angels to angels

Tough call, have to say I did add small angels to my 65GL and had no problem, did have a problem when adding the larger size.
Sexing, looks like a 50/50.
Good luck I would go small and at least 3 at a time if you think the 75Gl will hold so many Angels.
Don't see the point to keep so many in the 75Gl, you are asking for problems, I learned from my mistakes.
Angels pair up and then problems start.

Good luck
 
ditto what everyone else said - even six angels in a 75 will be too much when they hit maturity and start pairing off, IMO. I've got a 90g with 6 angels in it. The smallest's body is the size of a silver dollar, and the largest is now about 3" accross (not counting tail). My two silvers have paired up (no spawn yet), and as a result, the tank seems crowded. The silvers defend half of the tank from the other angels, and there's tons of posturing and squabbling going on. It's JUST posturing, and no actual damage being done, because it's a large, heavily scaped, densely planted tank. I can't see leaving all six of them in the 90g once they form more pairs - some will be moved to the 60g I've got coming, or I may move a pair to my new 30.

That's my long way of saying don't buy more fish - it won't fix the territory problems. If you do a really good job of scaping your 75, then everyone *might* live peaceably in it, but really, you'd be best to either trade in the pair, trade in the unpaired angels, or keep the pair in the 40 and move the others to the 75.
 
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