Phyto Help/question

[DRCOOK97]

So i started some Iso G. About 2 weeks ago and even after sterilizing everything i thought i lost the colony. The water went completely clear and i didnt see any coloration at all. My son read to add a little more F2 and there is a possibility of it reviving. Its been about 3 weeks now and this explosion of yellow color happened in the last 2 days. Is this possibly the Iso or something else all together? Nano behind at day 8 for color reference. If its something else what could it be?

 

[Naekuh]

The only way one could answer this question is if you put it under a microscope.
Otherwise there is almost no knowing what it is, if you did have a complete culture crash.