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R2R Username: @Tigahboy
Build Thread:
Tigahboy's Macroalgae Tank(s)



Greetings from Seattle, Washington! I’m super honored and thrilled to be featured this month on Reef2Reef. Although I go by Tigahboy and tigahboy.h2o online and in social media, my real name is Dennis, and I’ve been keeping saltwater tanks since 2004.

Although I’ve kept many different types of saltwater reef tanks over the years, I found my true passion in keeping macroalgae display tanks (perfectly acceptable to also call them “marine planted tanks”, but in all events, please do not call them “refugiums” J). I believe macroalgae in our hobby is very underappreciated, and believe you can keep a truly colorful saltwater tank with just macroalgae. I too once only appreciated macroalgae from a totally utilitarian perspective – either as a nutrient exporter in a refugium or scrubber or as food for fish. But I believe they can be the primary star of a reef tank. The diversity of colors and shapes in macroalgae is truly remarkable, and I believe we have only really scratched the surface in terms of what can be kept in our tanks.

I currently have three macroalgae tanks (details below) plus a grow-out tank to collect my extra trimmings from my main tanks and I just recently set-up a tiny 2 gallon pico which will also house macroalgae.

What specifically led you to decide to start keeping macroalgae tanks?

I’ve always been drawn to the aesthetics of freshwater planted tanks. They can really be true works of art. When I planned my first macroalgae tank (the UNS 45A), I wanted to replicate the look and feel of a freshwater planted tank but with saltwater components. Macroalgae seemed like the perfect fit for that purpose.


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System Profile(s):
  • Display tanks: UNS 5N (4 gallons), UNS 45A (9 gallons), and UNS 60S (10 gallons)
  • Glass or Acrylic: All low-iron glass
  • Stand: I like to integrate my tanks with the rest of my home, so I have my UNS 5N and 45A on a West Elm mid-century console and I have my UNS 60S on a granite countertop.
  • Sump: None
  • Grow-out tank: 10 gallon Aqueon
  • Protein skimmer: None (macroalgae appreciate dirty water)
  • Carbon/phosphate filtration: None
  • Water circulation: I have a Nero 3 on my UNS 60S, Hygger Wave Maker on my UNS 5N, Sicce Syncra Silent 0.5 on my UNS 45A, and an Aqamai KPS on my grow-out tank.
  • Lighting (display): Twinstar 30B for my UNS 5N, Twinstar 450E for my UNS 45A, and Twinstar 600S for my UNS 60S.
  • Lighting (grow-out): Nanobox Mini Tide
  • Calcium/alkalinity/magnesium dosing equipment: Manually dose
  • Auto top-off: Manually dose, but I do have two XP Aqua Duetto ATOs and a Smart Micro ATO ready for when I go out of town.
  • Heating/cooling: I use the Cobalt Neo-Therm on all my tanks.
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UNS 5N Getting Started

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UNS 60S Getting Started

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Tigahboy's Grow Out Tank​

Water Circulation and Flow Summary and Objectives:

For my macroalgae tanks, I try to have medium, random flow. So I use wave makers for all my tanks. I really like my Nero 3 the best, but my Hygger Mini Wave Maker works really well for pico tanks and it’s the smallest wave maker I’ve found in the market.

Water Parameters:

  • Temp: 75-78 F
  • pH: 8.2
  • Salinity: 1.025
  • NO3: 20-30
  • Ca: 480
  • Alk: 9
  • Mg: 1400
  • PO4: 0.1
  • Ammonia and nitrites: 0
What’s your ideal temp for macros? I've heard high heat causes them to melt.

Some macroalgae, like Sargassum, do prefer cooler temperatures. I keep my tanks anywhere between 75-78F.

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What salt mix do you use?

I’m currently using Reef Crystals.

What kind of rock did you start with?

I prefer to use live rock because of the biodiversity and you also can get all kinds of cool hitchhiker macroalgae. I’ve had all kinds of really cool macroalgae sprout up out of nowhere from my live rock. I know unwanted macroalgae is a fear of many reefers, but I welcome it for my macroalgae tanks. All of my live rock is from KP Aquatics.

What is your substrate?

I’m a big fan of Caribsea and use Fiji Pink and Special Grade for my various macroalgae tanks.

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Calcium/Alkalinity/Magnesium Summary and Objectives:

Calcerous macroalgae, such as halimeda, do consume calcium, and while I do not believe macroalgae consume as much calcium as coral overall, they do benefit from dosing calcium. Magnesium and sodium bicarbonate are also utilized by macroalgae as well. To meet these needs, I dose ATI Essentials Pro daily.

Are you dosing anything else for your reef health (carbon dosing, aminos, etc.)?

I currently dose Brightwell Aquatics ChaetoGro (fertilizer), NeoNitro (nitrates), and NeoPhos (phosphates) daily. I believe this combo works really well to supply macroalgae with all the nutrients/elements that they need to thrive.

Are lighting needs for macroalgae tanks different from reef tanks? If so, in what ways? Also, how do you choose lighting for a macroalgae tank?

While I believe macroalgae can tolerate a wide variety of lighting conditions, I think full spectrum lighting (6500K) is ideal lighting for macroalgae. A lot of freshwater planted tank lights are within this spectrum, so I gravitate towards those lights for my tank. Currently I am using Twinstar brand freshwater planted tank lights for all my macroalgae display tanks and have had good results. But I know plenty of people who grow macroalgae under reef lights as well, and a lot of reef lights are highly adjustable and allow you to adjust spectrum.


Do you have to worry about PAR numbers or the possibility of burning your macros?

Not too much because I think macroalgae can tolerate a wide range of lighting. But some red macroalgae, such as Gracilaria hayi, actually look better (more vibrant and deep red) under lower intensity lighting. My blue hypnea pannosa also becomes bright blue under higher lighting as well. Just like coral, I’d try out different placements and see where they thrive best in your tank.

  • Display tanks: 8 hours
  • Grow-out tank: 8 hours
Filtration and Water Quality Summary and Objectives:

When keeping macroalgae tanks, I believe you can keep things pretty simple in terms of filtration. A protein skimmer, for example, would filter out the very nutrients that macroalgae would need to thrive. For my macroalgae tanks, I usually rely heavily on biological filtration through a combination of live rock and bio media to supplement and also run filter floss as mechanical filtration. Last but not least, the macroalgae, of course, is also great form of natural filtration in itself, and they do a great job of keeping my tanks clean. I barely have any diatoms in my tank as a result.

What is your export strategy?

Since I am currently keeping only macroalgae tanks, of course my sole method of nutrient export is macroalgae. They keep my tanks super clean. Keeping up with their nutrient demands is probably the most challenging aspect of macroalgae keeping given my nutrients will quickly zero out unless I supplement nutrients into my tanks.


Do you have to worry about your macroalgaes going sexual?

I think there’s a lot of fear about macroalgae going sexual – the survival response where macroalgae suddenly release all of their spores in response to a deficiency in water parameters or lighting. The main issue with macroalgae going sexual is the sudden nutrient spike and increase in CO2 that results from macroalgae releasing all of its contents back into the water. With spores everywhere in the tank, there could also be more macroalgae sprouting up in new places (not necessarily a bad thing for us macroalgae keepers though). I think all of this is manageable if you act fast and do the following: 1) remove all translucent/dying parts, 2) do a big water change (as much as you can), and 3) run activated carbon for 24-48 hours. I’ve done this a few times already and did not have any ill effects.

Can you share some of your methods/tips for keeping things as you want them?

Regular trimming is a must for macroalgae tanks. Just like freshwater planted tanks, regular trimming helps promote healthy growth and avoids restriction of flow in the tank. Also in terms of aesthetics, keeping your macroalgae trimmed will help ensure they stay where you want them to be in the tank. I use freshwater aquascaping stainless steel tools to trim and maintain my plants. I do prefer the black-coated ones though since they seem to rust less.

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What is your maintenance routine?

Daily: Dose supplements, top-off, and feed my tank inhabitants
Weekly: 20% water changes and macroalgae trimming
Other: Every few days I replace out my filter floss and spray RO/DI water on my mangroves. I do a deep clean of my pumps and equipment twice a month.


Tank Inhabitants—Fish: (Please List)
  1. Two Blue Sapphire Damsels (Spingeri) in my UNS 60S
  2. Pair of Ocellaris clownfish – Darwin and a classic – in my grow out tank
  3. Six masked gobies in my UNS 45A
  4. Balloon mollies that were acclimated to saltwater in my grow out tank
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Other Invertebrates:
  1. Peppermint shrimp
  2. Sexy shrimp
  3. Dwarf zebra hermits
  4. Scarlet hermits
  5. Astrea snails
  6. Florida Ceriths
  7. Dwarf Ceriths
  8. Various feather dusters
  9. Pods. So. Many. Pods.
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Tank Inhabitants— Macroalgae:

I have over 20 species of macroalgae among my macroalgae tanks (and that doesn’t even include my bryopsis, bubble algae, and hair algae!). Given there aren’t a lot of resources out there on macroalgae and there aren’t many keeping them, I find it challenging to positively and accurately identify all the different types of macroalgae being kept in the hobby thus far. But here’s my best shot at a complete list of the different species in my tanks:
  1. Caulerpa prolifera
  2. Caulerpa taxifolia
  3. Caulerpa racemosa
  4. Gracilaria hayi
  5. Gracilaria tikvahiae
  6. Gracilaria parvispora / Red ogo
  7. Halimeda
  8. Mermaid’s fan
  9. Mermaids cup
  10. Branching coralline algae (2 different kinds)
  11. Cotton candy algae
  12. Codium
  13. Botryocladia (3 different kinds)
  14. Ulva / Sea Lettuce
  15. Galaxaura
  16. Blue Hypnea pannosa
  17. Red Palm
  18. Blue Scroll
  19. Sargassum
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Fish and Tank Feeding:

I feed all my tanks a variety of Reef Nutrition products daily: Phyto-Feast, Oyster-Feast, Roti-Feast, R.O.E., and Arcti-Pods

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How did you decide what to keep in your tank?

Finding macroalgae is actually pretty challenging. So I am not picky about what I stock for my macroalgae tanks. Whatever I can find, I usually buy up quickly.

Would it be possible to have a hybrid macroalgae/reef tank that has a balance of macroalgae and corals? How hard would this be? What would be some of the challenges?

Many reefers do keep macroalgae and coral together successfully, but just like any mixed reef, compromises will need to be made. A macroalgae-specific tank is the most ideal of course to meet their needs. For instance, full spectrum lighting may be more ideal for macroalgae but less ideal for coral that require more blue spectrum. In addition, when being kept together, there is always the possibility of macroalgae spreading over coral since they grow so quickly, but that can be controlled with regular and frequent pruning. Also, for more sensitive coral like SPS, macroalgae going sexual could pose issues as well, but that can be mitigated as described below.

Any stocking regrets?

I regret adding Scarlet hermits. I’m pretty sure they are munching on some of my macroalgae, and I will probably find them new homes soon.

Any fish, invert, or coral you will NEVER keep?

Tangs! Have to keep my macroalgae safe.

What do you love most about the hobby?

The blend of science and art. I love being able to create a work of living art out of a reef tank. I find every reef tank to be an expression of each tank owner’s personality and artistic style. We all have to play part-time scientists as well to truly keep our tank inhabitants happy, and I find that aspect of the hobby to be equally as rewarding.

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How long have you been doing this?

I started my first reef tank in 2004. I’ve been in and out of the hobby a few times for moves and such, but I’ve never been away from tanks for very long.

Who was responsible for getting you into the hobby?

When I was a young kid, I used to go to a local fish store every weekend (and pretty much every day during the summers). The owner there, named Al, was really my mentor and helped teach me everything I knew about keeping fish tanks. I only kept freshwater tanks back then, but Al really instilled in me the passion for aquarium keeping.

Who or what in the hobby most influences/inspires you?

All of my macroalgae tanks have been largely inspired by freshwater planted tanks because while I really appreciate those tanks and their aquascapes as true works of art, I’m a salty guy at heart and love keeping saltwater tanks. I find a lot of parallels between keeping macroalgae and freshwater planted tanks, so I find a lot of tools and tips from the freshwater side of the hobby applicable to keeping macroalgae tanks.

If you could have any tank, what size would it be and why?

I’ve kept mostly just nano tanks (20 gallons or less), but I would really like to set up a macroalgae display tank in the 75 gallon range.

Favorite fish?

Basic clownfish!

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Favorite macroalgae?

I would have to say Sargassum is my favorite. It has a brilliant gold color and its unique blades and air bladders are really remarkable.


Favorite invert?

Feather dusters! They are really beautiful and add nice movement to any tank.

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How do you typically get over setbacks?

I try to be as comprehensive as possible in my research and solicit feedback from fellow reefers to tackle setbacks. I’m pretty patient as well, so I try not to react too much to setbacks and obstacles until I’ve given some real time to tackle them. I had dinos in literally all of my tanks at one point and it was a bit overwhelming, but I overcame them through extensive research and patient treatment.

Have you faced any major challenges with this particular tank, and if so, how did you overcome?

As I mentioned above, the biggest challenge I’ve faced was dealing with dinoflagellates. Macroalgae will deplete all nutrients in your tank easily, so it’s no surprise that these tanks can be prone to dinos. I did a ton of research and chatted with other reefers who overcame them to come up with my own treatment plan, which involved increasing nutrients and biodiversity, raising the temperature of my tanks, and running a UV sterilizer. It took many weeks to finally win the battle, but I haven’t had any dinos since. Knock on wood.

What's the best thing you ever bought for your tank?

My favorite piece of equipment is my Nero 3. It’s an amazing wave maker and perfect for nano tanks.

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What are your future plans for improvement/upgrade of the tank?

I hope this year to set-up a larger macroalgae display tank with a sump to grow out more macroalgae. I would run them on a reverse photoperiod.

Also, a new pico is in the works.

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New Pico Project​

Any special tips for success or advice you'd like to share with other reefers?

I think there’s a real bespoke quality to reefkeeping and husbandry. Of course there are best practices and minimums that should be observed, but I think each reefer should tailor that information to his/her own tank. Every tank (and even macroalgae tank) is unique and a multitude of factors allow some methods to succeed in some tanks but not in others. So the best advice I can give is to not take every piece of advice online as fact (and be mindful that what works for you may not work for everyone else), but more of a general guideline that should be customized for your own unique tank.

Final Thoughts?

I think macroalgae keeping in this hobby is a real growing trend. I see more and more aquarists from both the saltwater and freshwater side setting up macroalgae tanks now, and I hope this super niche side of our saltwater hobby continues to grow. I think the main challenge to setting up and keeping a macroalgae tank is finding them. They are still very difficult to find, especially so for reef hobbyists outside of the U.S. Only when there is a real demand for macroalgae will we start to see it become more readily available in the hobby, whether through collecting in the wild (hopefully responsibly) or aquaculturing (which would be ideal). I hope you will consider giving macroalgae a try, and ask your LFS to get more macroalgae!