» Posted by on Mar 21, 2014 in Blog, Reef Aquariums | Comments Off on Reef Aquariums – A look at Aesthetics, Unwanted Algaes and Parasites Part 2

Aggressive encroachment will involve the two most common reef attackers and the most difficult to beat, Aiptasia sp. and Anemonia sp. Their resilience is due to the

Auriga Butterfly

fact that water parameters do not matter. They thrive on the same things your coral use to live – light, nutrients and room to grow. The effect is outnumber and attack by irritation. Aiptasia have a powerful sting for their size. They can cause a coral to stay closed   thereby causing its demise – if you can’t open you can’t feed!! The coral then dies leaving prime real estate for Aiptasia to live. A prettier cousin, Anemonia, looks nice, green with bulbous tips, but deceivingly stings and propagates even faster, taking over a tank in weeks.
Cause is very easy in this case. It is merely introduction. Unknowingly on rock or a purchased coral, the aquarist introduces this killer into an ecosystem with all the parameters it loves.
Unlike algae problems, cures of aggressive encroachment by Aiptasia and Anemonia sp. are quite simple physical removal and natural predation (my favorite). Just like introducing a pine snake to control mice in a grain solo, these pests also have natural-predators or they would be taking over the oceans. The key is finding the best predator that will not harm our other invertebrate “friends.” In my 15 years of this trial and error, I will give you a list of a dozen natural predators. Some will destroy them in a few days, but as in the wild, must adapt to a new “food source” to survive. Once they’ve done their job by removing Aiptasia, I feel all must be unfortunately “removed” to prevent predation of other species:

  • Chaetodon striatus (butterly spsc.)
  • Chaetodon lunula (butterly spsc.)
  • Chaetodon fasciatus (butterly spsc.)
  • Chaetodon kleinii (butterly spsc.)
  • Chaetodon auriga (butterly spsc.)
  • Chelmon rostratus (butterly spsc.)
  • Chelmon muelleri (butterfly spsc.)
  • Chelmon marginalus (butterfly spsc.)
  • Bergia verrucicomis (nudibranchs)
  • Lysmatta wurdemanni (peppermint shrimp)
  • Rhynchocinetes uritai

There are a few parasites that we encounter due to live rock and coral introduction. This alone can be a ten page list, so here are the most common three I have encountered.
Asterina sp. starfish is a “cute” little white starfish that can multiply rapidly in a closed system where no predator exists. These are commonly seen before lights come on then disappear for shelter in rocks. They are opportunistic feeders on coral and can slowly kill and go unnoticed. Once again, physical removal and natural predation by the harlequin shrimp Hymenocera elegans can decimate an Asterina population, but once again other echinoderms are maybe in danger.
Heliacus sp. is a very nice looking snail, always seen on zooanthid rocks (polyps). If everyone knew how many countless hours I spend combing my polyp rocks for predatory snails, it’s a wonder anything else gets accomplished!! These “cute” snails, including Philippia and Architectonica sp., are actually like little vampires. They have a proboscis (hollow harpoon/tooth) that impales the polyp or anemone and sucks out the fluid. Physical removal is the only means – I know a natural predator must exist or overpopulation would occur I just have not found it yet (sorry!).
Lastly we will touch on a confusing one because some believe the red planaria (Convolutriloba retrogemma) is only an opportunistic feeder on autotrophic invertebrates (light- loving). The red color you see in this planaria is actually ingested zooanthellae from another invertebrate (parasitic?). Singly, they are harmless, but can quickly overtake and swarm a tank. These are easily taken under control, since they use the algae as a food source and diminish the light to slow the splitting. Secondly, sudden changes also affect planaria (temperature and salinity). Physical removal is always a great tool. Hundreds can be siphoned out with airline tubing (thereby not draining a lot of water). Lastly, my favorite, natural predation is always the finishing touch to fix the end of a problem (low planaria load, easily consumed). Here are some decent fish predators:

Harlequin Shrimp

  • Macropharyngodon sp. (small wrasses)
  • Anapses sp. (small wrasses)
  • Synchiropus sp. (small wrasses)
  • Pseudocheilinus sp. (small wrasses)
  • Halichores sp. (small wrasses)

In my experience, the best planarian eater by far is the blue/black velvet sea slug (Philinopsis sp.). This beautiful nudibranch vacuums them up as it passes over them (the planaria actually scurry away as it approaches) quickly getting the population under control. Sadly, the nudibranch is short lived so first physical removal then introduction of natural predator.
Concluding this synopsis, I only began to scratch the surface on this topic because there are many more problems and many new ways to treat them. I will never say I am the expert or the authority on any topic because I must honestly say I still am constantly learning as much from our clients as I hope they are learning from me. All I can offer is my experience and trials and errors maintaining these small aquatic ecosystems.

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