While lighting is important, maintaining excellent water quality may actually be the biggest factor in growing a good crop of Coralline. Like hard corals, Coralline Algae is calcareous by nature, requiring many of the same things corals do in order to flourish:
SG apx 1.024
Calcium - 350 to 480 ppm
Carbonate Alkalinity - Between 2.5 and 4.0 meq/L (7-12 dKH)
Low Phosphates (Close to Zero)
Low Nitrates (5 ppm or lower)
Many aquarists have found that performing regular water changes will keep the phosphate
levels in check as well as keeping the calcium, alkalinity and strontium at or near their optimum levels. Others have found that using Mangroves
in their systems has been a simple and inexpensive method for reducing nitrates and phosphates and that using calcium and strontium additives produces the same or better results without the constant expense of sea salts and RO/DI water required for water changes.
Many aquarists have also found that using a good protein skimmer goes a long ways towards controlling nitrates and phosphates.
Leroy, from GARF makes the point for the use of additives: "We have found that by using SeaChems Reef Builder and Reef Advantage (Compare
Prices) in alternating doses in our make-up water we have had no trouble keeping both the calcium and alkalinity at the proper levels for rapid coralline growth. This simple method of treating our make-up water also keeps the strontium level in our grow out tanks high enough for the coralline algae to thrive."