Just some thoughts...
I'm currently running a 55g with 10g fuge. The display tank was stocked with mainly base rock, and 3 pieces of live. Coraline algae on the live consisted of green, purple, pink, red, and orange. Lighting was an old 40w "aquarium" NF. This lighting was maintained for several months.
During this time I observed the following. With the low level of lighting the green coraline is the only color to have shown noticeable growth. It had spotted a majority of my rock, and grown extremely well on 3 coral skeletons, and empty snail shells in the tank. Dark purple spotted in a few places, but I had to search to find them. Two small spots were located on the front glass. Bright purple had an initial die-off, followed by basic stasis. No further die-off, but no growth. What was initially a pink rock has mostly died off to an even tan. Red and orange appeared to also be in stasis.
One week ago (approx) I upgraded to 210w of PC
lighting. This included 2 10k bulbs and 2 50/50. 50/50's are rated as being 1/2 10k and 1/2 03
. While I'm not entirely sure the actinic is true 03
, it does display a nice purple spectrum, and not the smurf blue I was dreading. In the last week there has been massive green die-off. The coral skeletons that were begining to look like live green coral is essentially dead. The mature algae on the rocks appears to be fine, but the growth througout the tank has visibly slowed. However, the purple spots on the front glass have visibly grown, and additional spotting throughout the tank can be found. I have also found red spotting on the base, as well as the other established rocks. Orange is so far not growing, and pink has yet to make a reappearance.
On the 'fuge, I initially ran an 18w NF plant bulb 24/7. the fuge is stocked with caleupra grape macro. After updating the display lighting I switched to a reverse cycle, lighting the 'fuge only when the display is shut down for the night. After 1 week of reverse cycle, the macro began going sexual and nitrates have climbed significantly in the system. The apparent lack of export combined with the higher intensity lighting has led
to an algae bloom. 'Fuge lighting is back to 24/7 as of tonight and I expect the algae to reduce in time.