DT's, Golden Pearls etc

[Biogeek]

delphinus: You don't really have to have a hugely over-powered skimmer on your system to remove phytoplankton - just a really efficient one. Although most skimmers didn't really remove much phytoplankton from the water when DTs first came on the market, many of the high efficiency skimmers out there today (like the ETS, HSA, AquaC, etc.) certainly pull out phytoplankton pretty well...

DJ88: Glad that the article is useful. I think I cited David Cripe's article on phytoplankton culture (the same species of phytoplankton can range from highly nutritious to down-right toxic depending on how they are cultured and exactly when they are harvested), and discuss the results of growth trials of phytoplankton cultured on different media (although now that I think about it, that might have been cut for length). Anyhow, the basic story is that it is easy to take a single culture of phytoplankton, split it between several vials, and grow each of them on a different growth medium in the lab. Each culture grown in this way will end up producing phytoplankton of different nutritional value. I presented data in my talk at the last MACNA showing how much faster copepods grow and reproduce on phytoplankton cultured with the recipe that I give in the GARF article above compared to liquid plant fertilizer drops from Wal-Mart. That is the point I was trying to make, and although it is certainly possible to culture phytoplankton at home, even with my experience and facilities to grow phytoplankton for my research, I'd rather buy it ;)

Siverfish: most of the marine animals that feed on phytoplankton do better with continual small doses of food rather than occasional big doses. They can't really take advantage of a big pulse of food every couple of days, and you will probably notice more small critters in your tank if you feed the same total amount at about 3 ml per day, rather than 10 ml every 3 days...

EmilyB: Even established tanks don't produce enough phytoplankton to support the growth of obligate suspension feeders (such as flame scallops for example). There are some planktonic algae that grow well in established tanks (primarily diatoms), but most of them are eaten pretty quickly, and unless you have a really high nutrient load (which would almost certainly lead to you growing a lot of other algae in the tank too), there simply isn't enough phytoplankton to supply any animal that requires it with a consistent food supply.

If you have only symbiotic corals that get enough light and can capture excess fish food, then that probably doesn't matter to you. If, like Tony above, you have juvenile clams that gain more energy from suspension-feeding than from their symbiotic algae, or some species of obligate suspension feeding invertebrate in your tank, then you'll have to find some way to supplement the amount of phytoplankton in your tank to give them a reasonable chance of survival...

Rob