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Macroalgae
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Macroalgae
- All Macroalgae
- Red Algae (Rhodophyta)
  
  All Red Algae
  Iridescent Blue Algae
  Purple Algae
  Fluorescent Algae
- Green Algae (Chlorophyta)
  
  All Green Algae
  Caulerpa Algae
  Non-Caulerpa Green Algae
  Calciferous Green Algae
- Brown Algae (Phaeophyta)
- Bundle Packs
- Beginner Species
- Shop by Genus
  
  Acanthophora
  Acetabularia
  Alsidium
  Botryocladia
  Bryothamnion
  Caulerpa
  Chlorodesmis
  Chondrus
  Codium
  Coelarthrum
  Coelothrix
  Corallina
  Cryptonemia
  Cymopolia
  Dichotomaria
  Dictyota
  Digenea
  Eucheuma
  Fauchea
  Galaxaura
  Gelidium
  Gracilaria
  Halimeda
  Haliptilon
  Halymenia
  Heterosiphonia
  Hypnea
  Jania
  Laurencia
  Lobophora
  Nemastoma
  Neomeris
  Neurymenia
  Ochtodes
  Padina
  Penicillus
  Portieria
  Riphocephalus
  Sargassum
  Scinaia
  Turbinaria
  Udotea
  Ulva
Invertebrates & Cleanup Crew
- All Invertebrates
- Snails, Slugs, & Conchs
  
  All Snails, Slugs, & Conchs
  Turban & Trochus Snails
  Cerith Snails
  Nassarius & Marginella Snails
  Dove Snails
  Nerite Snails
  Cowrie Snails
  Conchs
  Predatory Snails
  Other Snails
  Slugs, Hares, & Nudibranch
- Hermit Crabs & True Crabs
  
  All Crabs
  Hermit Crabs
  Porcelain Crabs
  True Crabs
- Shrimp
  
  All Shrimp
  Cleaner Shrimp
  Anemone Shrimp
  Boxer Shrimp
  Pistol Shrimp
  Mantis Shrimp
  Other Shrimp
- Sea Stars, Cucumbers, & Urchins
  
  All Echinoderms
  Sea Stars
  Serpent, Brittle, & Crinoid Stars
  Sea Cucumbers
  Sea Urchins
- Clams & Other Bivalves
  
  All Clams & Bivalves
  Tridacna Clams
  Clams & Mussels
  Scallops & File Clams
  Oysters
- Fanworms
- Anemones & Jellies
Nano Fish
- Gobies
- Seahorses & Pipefish
Macroalgae Rocks, WYSWYG, & More
Sponges & Tunicates
Gorgonians & Other Corals
Fertilizers & Dry Goods
Gift Cards
Sales & Promotions
Care Sheets, Tips & Tricks, and Other Blog Posts

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Collection: Alsidium

The Alsidium genus features comb-like, bristly branches.

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Our mission

Our mission is to provide a reliable and reputable source for live ornamental macroalgae. We wish to extend the beauty of algae to other hobbyists who are eager to grow beautiful marine planted aquariums!

Live Arrival Guarantee

Live arrival with FedEx 2Day is guaranteed on algae not marked as sensitive in the description of the algae, with an exception for some weather conditions. All corals & invertebrates must be shipped via FedEx Priority Overnight shipping, and will be marked in the description. Please see our Terms of Service for our full LAG Policy.

Livestock Disclaimer

Macroalgae is generally safe with most snails, hermit crabs, shrimp, and fish. With this in mind - you should research your livestock and compatibility prior to purchasing. We are never liable for macroalgae eaten by tank inhabitants.

Hitchhiker Disclaimer

Macroalgae provides a biodiverse haven for many benthic creatures - and we are therefore unable to guarantee that organisms will not hitch a ride on your algae. This includes other algae, plant-like protists, anemones, echinoderms, annelids, crustaceans, and other invertebrates. MosaicMacros is never responsible for these animals, and by purchasing with us you are acknowledging the possibility of hitchhiking organisms.

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