Reefball care

Dear Curio:

Macroalgae (marine plants) are generally very easy to care for, and the Ulva Sea Lettuce that comes in the Reef Balls is even more so. It does not require any particular care other than low-to-moderate light levels. Basically, it can be treated exactly like the Ulva amphipod mats provided by Indo-Pacific Seafarms (IPSF), as described below:

"Reef Amphipod Breeding Kit. Amphipods – small, shrimplike crustaceans of the genus Grammarus – are among the best invertebrate diversity builders you can add to a reef tank, sump or refugium. Our Hawaiian Reef Amphipods mate and reproduce readily in captivity. They consume enormous quantities of diatoms, hair algae and other nuisance algae. They are also a healthy live diet for all types of clownfishes, angelfishes and Mandarin gobies.We ship our captive-bred Reef Amphipodstm nationwide daily, and we’ve learned that their preferred breeding habitat is a lush green mat of Ulva macroalgae – the ‘Pod Mat. You can create your own amphipod farm by floating one of these amphipod mats under low light in a well-aerated sump, refugium or dedicated 10-gallon breeding tank. Seed it with amphipod breeder specimens which we provide. A twice-weekly addition of our enriched ‘Pod Flakes (just a pinch!) provides ample nutrient input and trace elements. Our Reef Amphipod Breeding Kit gets you started with all the right components: adult and sub-adult reef amphipods (at least 25 specimens), a thriving 3" x 3" mat of Ulva macroalgae and enough enriched ‘Pod Flakes to last for several months. Grow your own!"

The Ulva in the Reef Balls doesn’t really need to be trimmed or cut back, although some other macroalge, such as the fast-growing Caulerpa species, does require pruning. For example, I prefer decorative marine plants or macroalgae in a variety of shapes and colors and color — reds, browns, golds, and yellows in addition to green varieties, some tall and feathery, some short and bushy — to provide natural hitching posts and shelter for my seahorses. I like to start with a mixture of red and gold Gracilaria (Ogo) and artfully arrange them around a lush bed of assorted bright green Caulerpa. Any of the plumed (feathery) or long-bladed Caulerpa would be ideal for this, such as Caulerpa sertularioides, C. mexicana, C. ashmedii, C. serrulata or C. prolifera. The result is a colorful macroalgae garden with a very nice contrast of colors (reds, yellows, greens, and brown) and interesting shapes. A tank heavily planted with macros such as these is a lovely sight and mimics the seahorses’ natural seagrass habitat well.

As an added benefit, the macroalgae act as an excellent form of natural filtration, reducing the available levels of phosphates and nitrites/nitrates. Be sure to prune and trim back the fast-growing Caulerpa regularly; when you remove the clippings, you’re exporting phosphates, nitrates and other nutrients from the tank, thereby helping to maintain good water quality, and pruning the runners helps keep it from going sexual.

When pruning or trimming back macroalgae, take care not to actually cut it. Remember, you’re not pruning hedges or trimming trees — the idea is to carefully pull up and remove continuous, unbroken fronds. Simply thin out the colony of excess strands, gently plucking up convenient fronds that can be readily removed intact. A little breakage is fine, but cutting or breaking too many strands will result in leaching undesirable substances into the aquarium water as the Caulerpa’s lifeblood drains away. Too much cutting or breaking can thus sap the colony’s strength and cause die offs or trigger the dreaded vegetative events that judicious pruning otherwise prevents.

If you’re concerned about your ability to maintain and control of Caulerpa properly, just use a different forms of macroalgae that grows less rapidly instead and you can get the same sort of benefits at relatively little risk. In that case, some of the other macroalge you may wish to consider are Gracilaria, Ulva, Chaetomorpha, and Chlorodesmis. Hawaiian Ogo (Gracilaria sp.) are bushy red-to-brown macros that do well under low light levels. Sea Lettuce (Ulva sp.) are deep green sheets of algae that do best under a little stronger lighting. Maiden’s Hair (Chlorodesmis sp.) are bright green tufts or clumps of very fine-bladed algal mats to grow attached to small rocks. All of these types of macroalgae are much less prolific and slower growing than Caulerpa. However, like all macroalgae, they should still be harvested periodically in order to export the excess nutrients they have consumed.

Aside from red and brown Gracilaria and the bright green Ulva and Maiden’s Hair, some seahorse keepers also like the Chaetomorpha turf algae. It can best be described as looking like the clumps of the colorful plastic grass we use to fill Easter baskets. It is popular because it is slow growing and doesn’t require the kind of pruning that Caulerpa needs, and because it it comes loaded with microfauna: miniature feather dusters, copepods and amphipods, tiny snails and micro stars. Sounds like another interesting marine plant that can add some extra variety to a lush bed of macroalgae.

Best wishes with all of your fishes, Curio!

Happy Trails!
Pete Giwojna