Caulerpa Macroalgae - Caulerpa peltata
Picture taken September 1999, Sony Mavica FD91 digital camera, no flash

To the left are pictures of Caulerpa peltata macroalgae I attempted to grow in my sump. It is a different morph of C. racemosa and most likely not its own species. I used to have several other species of caulerpa but this one lasted the longest. It eventually died out like the rest of the caulerpa species I tried.

I have tried several different Power Compact and Incandescent lights. I had little to no luck growing these under anything smaller than 60w of light. I had good success with 100w light and the growth rate was excellent.

Caulerpa Macroalgae - Caulerpa peltata
Picture taken September 1999, Sony Mavica FD91 digital camera, no flash

Once growth started to kick I had to trim this macroalgae back frequently. It was after one of these trimmings that this species of caulerpa went sexual and I lost all of it.

From Marine Plants of the Caribbean, Littler et. al., p.46:

"Rhizoid-bearing rhizomes give rise to small (1-3 cm) flat-topped (umbrella-shaped) uprights, each consisting of a small slender stem topped with a disc like cap (1.5-8mm in dia.); pale to dark green with a faint bluish sheen. A distinctive variety found in low-light habitats such as shaded mangrove roots, dark crevices, or the underside of ledges in the reef habitats, often intermixed with other alga species in turf communities. Found in 1-84 meters of water."

Caulerpa Macroalgae - Caulerpa peltata
Picture taken March 2001, Nikon Coolpix 950 Digital Camera, No Flash

This picture shows how full of caulerpa the sump typically runs two years later. It only took a few weeks to fill the sump up, but I figured it would be nice to show. This picture shows the sump in need of some pruning. I use my stainless steal scissors and trim down the caulerpa by about 50%. This makes for excellent nutrient removal from the system.

Shortly after this picture was taken it went sexual and I lost all of it.

The term "It went sexual" when talking about macro algae often confuses people. The macro algae actually switches to a sexual reproduction mode and starts to expel its insides. Your left with a limp pile of mush that used to be a vibrant caulerpa colony. It will not grow back, and I have never seen any of the spores start a new colony.

Weeks or perhaps months of stored nutrients are suddenly dumped back into the system and a significant system of nutrient uptake no longer exists. Not a good combo. This sudden increase in nutrients tends to fuel hair algae growth or cyanobacteria growth.