Planted Display Tanks

Attitudes about algae are slowly changing amongst marine aquarists. For so long, with all the struggles with benthic microalgae (turfs, films, etc.), we were sure that algae are 100% bad and a scourge to avoid. But with the rise of refugia (specifically planted refugia), we saw an emerging appreciation for them--at least for certain macroalgae. Now, we’ve started to see an uptick (albeit a modest one) in the use of macroalgae for purely ornamental purposes like planted display tanks. Could this latest trend be a sign of the coming of an age of marine gardening? We certainly hope so! Even many veteran saltwater aquarists remain completely unaware of how many beautiful macroalgae species there really are. Sure, their colors are restricted mainly to greens, reds, golden browns and the occasional blues; their variety of form, however, is astounding. A cleverly arranged display of “macros” that highlights their contrasting hues and shapes makes for a strikingly gorgeous exhibit indeed. Sure, you could certainly mix ornamental macro species with the more utilitarian ones in your refugium. But a planted display tank is an altogether different sort of aquarium system in terms of water quality. Sure, you can specially tailor lighting or substrate in the fuge to suit your macros’ needs. On the other hand, when it comes to water quality, you would have to make some compromises (mainly to the advantage of the “main” tank). This is why planted displays are necessarily stand-alone systems. So, what are these big differences in water quality? The most notable are nutrient levels! Really, you wouldn’t want to run nitrates or phosphates much higher than in your reef system for fear of microalgae outbreaks; the major difference here is that you might actually have to regularly replenish nutrients (i.e. fertilize) in a planted system due to the comparatively rapid uptake! Similarly, because macros can be trace element sponges, there is a greater focus on trace element replenishment. In this section, you will learn of the many attractive and interesting macroalgae species to be cultivated ornamentally, how to fertilize, what kind of lighting is best and how to limit competition from nuisance microalgae.