No such thing as an ideal set of numbers. Just look for appropriate ranges in the chemistry.
NSW alkalinity 1.5-3 mEq/l (can be higher), calcium is 380-420
ppm (can be higher) with a balanced
Mg of 3x that of calcium. Driving numbers higher will not gain accelerated growth from calcerous dependant organisms. They deposit
CaCO3 at the same rate wether it be lower or higher. The important point is to ensure these numbers are >>
balanced<< (<<must use internet expl). Again, you are not looking for exact numbers, simpley being in the right ranges is sufficient.
Lighting is also important. It's a misguided belief that more light will equal better growth. In fact, most types of coralline will do best in lower types of lighting and actually thrives in a true actinic spectrum. Generally speaking, purples, greens, orange and red corallines will be nearer the bottom areas' in a bright tank (or even shaded areas) while the light pink is in the higher regions of the tank. Each type responds differently.
One thing that definately does improve the spread of coralline is sporing the tank. The easiest method is to place a coralline encrusted rock in the vacinity of a powerhead where it can get directed flow. This will constantly spread coralline spores throughout the tank. Next is scraping the coralline carefully with a toothbrush or the like. It accomplishes the same goal but is a bit more work. It is also recommended to turn off the skimmer when scraping. Skimmers are very efficient at removing the spores. Give them an hour or so to settle out of the water column before resuming skimmers fuctions. The last resort is purchasing something that will spore the tank like
Garf's Grunge. I wouldn't recommend this unless it is only dry base rock in the tank. Above all, patience. Once things settle in and mature, you'd be suprised how quickly it spreads.
As far as the
PO4, zero is definately ideal (based on your kit anyway) or as low as possible.
PO4 actually inhibits corals and the like from depositing
CaCO3 and slows or inhibits growth of stoney organisms.
How is your tank set up and what are your current numbers?
Cheers
Steve
