Common post, thought I'd try....Overstocked?

Any male-female pair of platies is a breeding pair ;p

I think 4 weeks is the time from conception to birthing and then a week or two or three of rest between broods. I've read (last comment) that more often is possible, but I think this is mostly due to the large number of platies he is keeping.
 
Your not overstocked, but I'd get that pictus outta there. He'll end up getting bigger than the rest of the fish, and much up those shrimp and platies, as well as anything else smaller. Other than that your set, maybe get a few more Angels and have a nice shoal going.
 
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