Doesn't bga smell especially ...algae-ish? A strong, pungent smell. And the colour is more like bluish green (duh). Oops, saw your last post only after I submitted - ignore. heh heh.

But from the pix, can't really tell. Cruise, take a sample and do a smell test. I think Stan is correct to state a combo platter.

What I have done to combat my algae problem (please correct me if I'm wrong):
1. Manual removal as much as possible
2. If plants are overgrown, trim - especially mosses. Thick and unruly mosses always end up with hair algae IMO
3. Dose more (on the higher range of target ppm)
4. Shorten photoperiod to around 8 - 10 hours
5. Make sure C02 is reading 30 - 40 ppm
6. Regular and consistent water change
7. Introduce a photoperiod break of 3 - 4 hours during the entire photoperiod duration. (Didn't need to try this because my algae is thus far under control)

All of this methods (except #7) were used. And I'm running 72w for a 56liter tank. Again, please take this info with a pinch of salt as your results may vary. Good luck.

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The nose runs and the feet smell - go figure
Steven