How to tell if macroalgae is getting enough light

[AlmightyJoshaeus]

Well...how do I? My little 1.5 gallon pico has Halimeda opuntia and corraline algae. The Halimeda varies from dark green to light green depending on which part of the plant you are looking at, and all the plants produce numerous little bubbles during the day (I am assuming due to photosynthesis). Thanks

[Subsea]

Less light is always better than more light.  With red macros like Dragons Tongue, Halymenia digitata, under intense light the top is red and orange and the bottom is a dark burgundy.  I would expect your green macro to be darker in shaded area and lighter under intense light.  That is pretty much what I see on land plants.

[AlmightyJoshaeus]

OK! Thanks Guess they are doing well. I also had some Gracilaria that went from orangeish red, to pink with clear edges, to falling apart (turns out it was dead on arrival when I called the seller, so he refunded me...but it made me paranoid).