Yes i think 6 months is too late to seperate the males and females, i would get the males in seperate enclosures set up as soon as you can. You can keep 2 females in a 4X2 enclosure, so for three you are probably looking at 6X4 or at the very least least 6x2.5 in my opinion, you want to be sure they have enough room. Some say that 8 square feet is big enough for 3 which is about a 60 gal enclosure roughly but the bigger the better. As far as the ages, you want to house dragons only of the same size together, 1.5 months and 3 months probably is quite the size difference.
hope that this helps some, the young females can be housed in a smaller enclosure together providing that they are about the same size, but as they grow you will need to definatly expand the size of the enclosure, i would plan ahead now and start building something large enough, partition it off and as they need more room, remove or move the partition. Be prepared also that not all females get along and they may need seperate enclosures anyhow.
"Hey do you really think that 6 months would be to late to seperate them? If so i will start to get the new setups. Also another Question could I house 3 females in 1 cage that is about 5 times the length of the biggest female, 2 of the females would be 3 months old at the time and the other 1 would be 1 month 2 weeks old. Would they be to far apart in ages."
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reiko 

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