This week's been business as usual. During my reservoir refill, I did notice my pH pen reporting some odd readings. This may have been due to a low battery but needless to say, I changed the batteries and recalibrated.
Should be about... two more weeks? ha
Your best bet is to get beneficial organisms for roots. Someone mentioned hydroguard. I use this and have no algae issues. Having good organisms mean that bad organisms will be out-competed and won't be able to get a foothold.
Clean out your res very well again and start root bennies BEFORE algae sets in!