Caring for Your Macroalgae
Welcome to the Hobby!
Want to know how to care for macroalgae? Whether you're including macroalgae in a refugium or the display, here at MosaicMacros we strive to provide high-quality ornamental macroalgae for all your reefing needs. Let's take a dive into macroalgae care!
Lighting
Lighting for macroalgae is generally recommended to be full-spectrum. Most LED aquarium lights geared towards freshwater planted aquaria will support most macroalgae species. Actinic aquarium lighting created specifically for corals is generally not recommended for macroalgae, as the overly blue spectrum cannot support many of the more difficult species.
*Please contact us directly if you need any recommendations for lighting!
Flow
Flow is generally not overly important for macroalgae, though too much flow can tear and dislodge some of the more delicate species. Flow rate should be close to what is recommended for soft-coral tanks (as long as some water movement is present and surface agitation is strong, most macroalgae are not too picky ;).)
Nutrients & Water Chemistry
The most important nutrient for macroalgae is nitrogen, or nitrate. Other nutrients such as phosphorus are also important, but not nearly as important as nitrogen. Nitrogen and phosphorus are the two main macronutrients that should be tested often and kept up to par.
For our main macroalgae display, we keep the following water chemistry:
Nitrate: 5-20ppm
Phosphate: .02 - .1ppm
Nitrite: 0
Ammonia: 0
Calcium: 400 - 450ppm
Magnesium: 1250 - 1350ppm
pH: 8.1 - 8.4
Temperature: 72°F - 78°F
Micronutrients are also very important for macroalgae growth but are much more difficult to test for. Thus, we recommended dosing an all-around micronutrient fertilizer at least weekly. Important nutrients such as iron and iodine are often found in these micronutrient fertilizers which are essential for macroalgae growth.
*Please contact us directly if you need any recommendations for fertilizers!
Attaching & Planting Your Macroalgae
We’re often asked: “How do you attach your macroalgae?” There are a few ways!
Method One: Super Glue
For thicker/tougher species (Gracilaria, Botryocladia, Euchema, etc.) using super glue gel can often work very well for attachment. This is our least favorite and least recommended way for attachment, though, as the glue can often cause the macroalgae to melt at the base and can even kill more delicate macroalgae (such as Halymenia) - yikes!
Method Two: Zip-ties & Fishing Line
Attaching macroalgae to rocks via the tying method is one of our favorites! This process is often unstressful to the macroalgae and works very well for a plethora of species. Simply tie the algae to the stump of a frag plug or rubble rock and boom! Your macroalgae should stay put (as long as it isn’t dislodged by a critter in the tank.) NOTE: Tying macroalgae too tightly to a plug/rock can cause the algae to split or melt back. We recommend loosely tying the algae in place.
Method Three: Wedging
Our favorite method for attachment - wedging the algae in place! Wedging an algae between rocks and other algae works the best and is the least stressful for the algae, in our experience.
Want to learn a trick? Certain macroalgae (in our experience - Hypnea) can act as a natural “glue” for keeping other macroalgae in place. Hypnea quickly forms its own temporary holdfasts to keep the algae fastened to substrate - and it will also cling to other algae! We often use Hypnea to form a bond between delicate macroalgae such as Halymenia and Nemastoma to keep specimens from drifting away ;).
Method Four: The Sand Bed
Only certain macroalgae should be placed in the sand bed! Off the bat - all species from the Rhodophyta (red algae) or Phaeophyta (brown algae) phylum should never be submerged in the sand bed as they will melt at the base. Calcareous macroalgae including Penicillus, Riphocephalus, Udotea, and Halimeda may be placed in the sand bed. The Caulerpa genus will also glady grow in the sand bed.
Did We Miss Anything?
Let us know! If you have any further questions regarding macroalgae care please don’t hesitate to send us an email - we’re always eager to help and answer any questions you may have! ;)
DISCLAIMER: All information provided in this article is our own experience and may not work for everyone. There is no rigorous scientific backing to any of the claims made in this article, and all information is based on our own real-world experiences caring for 50+ species of macroalgae. In taking advice from our experiences in this article, you are acknowledging that the provided information may or may not work for your algae or your aquarium.