Possibly I am not too hot on my pregnancy detection as I let mine spawn without isolation. The guppy has quite a visible gravid spot however it doesn't look very boxed so the gravid spot may be natural colouration on the skin, if she is pregnant then I would say you are around 10 days off from her dropping. Her chest should start to go square and the gravid spot should become a lot more dark, Once she has dropped I find I get most rapid growth by feeding them crushed flake food 6 times a day, and then after the first week daphnia 2 times a day and crushed flake 4 times a day. You can set up your own daphnia farm by leaving a bucket outside in the sun for a while until the water acquires a good stock of algae then buy some from your lfs feed them normally to your fish then once the bag is getting low chuck the remnants in the bucket and you will have a healthy stock in a week or two. I find the best way to get them out is to run a net through the water when feeding the large fish but for the babies I use a squeezy bottle and suck up the smaller daphnia.