blue green algae

I'm having a problem with this stuff in my fry tank, It is in the window, so I know this isn't helping, but the tank has been there a few years, and its only the last few weeks or so that I'm having a bit of a problem.

Obviously with daily water changes I'm keeping it sort of under control, BUT in just over a week I'm going away for 2 weeks, so I'm not sure what to do? Hubby is OK at feeding my other tanks but I'm not sure he'll touch the water changes?

I have now blacked out 2 sides, so hopefully that will help a bit. I have some PhosEx which I used on another tank I had problems with, but is it safe for fry?? It says OK for shrimps, and they're sensitive, but I'm reluctant to put anything in the water I don't need to?

The fry are about the size of half my little finger nail, I've had so much trouble with spawns recently, I really don't want to lose this lot, for some unknown reason I've only lost about half a dozen which is fantastic!!, and  as far as I'm aware I've done nothing different, so why this spawn has been so successful I have no idea, maybe they like blue green algae?

Any suggestions please??

There are many different species of blue green algae, generally I associate them with excess nutrients in the water, and I've often found that fry raised in tanks with them don't thrive, although whether this is as a result of the water quality, or a direct response to the blue green algae, is hard to say.
If yours are thriving I wouldn't worry too much, but personally, once the present batch have moved on to larger quarters, I'd do a thorough clean before using the tank for any further batches.

OK thanks Rob, I'l leave the PhosEx till I return and hope hubby has managed to keep them alive for me