Reef Parasites

Identification, Consequences, Treatment of

Overview

• Pyramidellidea snails

• Red Bugs

• Acro Eating Flatworms (AEFW)

• Montipora Eating Nudibranchs

• Zoanthid Eating Nudibranchs

• Acoel worms (red planaria)

Pyramidellidea snails

• Commonly called pyramid, pyram or rice snails

Identification• Look for 1/8” snails on bottom and in all

crevices of the clam.• Clear jelly-like egg masses which will also be

on the clam’s underside or in crevices of its mantel

• When there are large numbers of snails on a clam it will make the clam pinch or not open fully and may be a sign of the snails

Consequences• Tridacnid clam killer as well as bivalves,

gastropods, polychaetes, echinoderms and polyplacophorans

• If left unchecked the snails multiply quickly: Their egg masses can contain hundreds of eggs. These eggs hatch after about 15 days, become sexually mature at about 45 days, and have a life cycle of about 120 days. So, two Pyrams today can become hundreds in a month and thousands in a few months

Treatment of Pyramid• Tools

– Soft Tooth Brush:For brushing around the edge of the shell and the byssal opening to avoid damaging any flesh

– Stiffer brush(s) for scrubbing the middle of the shell where you won’t be in danger of contacting the flesh

– Wooden Skewers for digging in crevices

Cont’d• Quarantine all new clams inspect them once purchased for egg

masses and snails and clean them off.• Pyrams are nocturnal. So about an hour or two after all lights

are out in the aquarium the Pyrams will start to come out to feed on their host. Fill up two containers that are large enough to hold the clam with aquarium water.

• Gently grab the clam and turn it so that the mantle is horizontal and slowly lift it out of the water. You never want to remove a clam from the water – especially a large clam – with the mantle pointing up (vertical) because clams can not support their mantles well while out of the water

• Brush sides with stiff brush, use soft brush to clean close to flesh and opening use the skewers to clean crevices of the mantel

• Scoop out the substrate from where the clam was to remove any Pyrams that might have been hiding there

• for the next four to six weeks you will need to repeat this cleaning routine two to three times a week, discarding the substrate as well. Even if you don’t see any snails, do the whole routine. After six weeks you can slow down to once a week for another six weeks

Cont’d• Possible Predators

– six line wrasse (Pseudochellinus hexataenia), the four line wrasse (P. tetrataenia) and the yellow coris wrasse (Halichoeres chrysus) that may eat Pyrams, however at best, these fish will only control the population, not eradicate them. Remember, Pyrams are nocturnal (active at night) and wrasses are diurnal (active during the day).

Size Reference

Egg Mass

Red Bugs

Identification• Red Bugs are flea like copepods which

are yellow with a red head

• Primarily affect smooth skinned Acro’s and seem to prefer Nanas and Validas

• Usually acros that are highly infected will loose polyp extension as well as a loss of color.

Consequences • In small numbers they will go unnoticed

unless you have seen them before.

• Once in large enough numbers they will smother acros causing loss of color, polyp extension and eventually death of coral.

Treatment of Red Bugs• Treatment medicine is Interceptor

– Which is heartworm treatment for dogs and must be obtained by a Vet. Pills are for 51-100lbs dogs

• First type of Treatment: Quarantine Tank– Fill a small tank or container with your tank water and a

small power head.– Take one pill and use a spoon to crush it into a powder. You

will only have to use a small amount as one pill is enough treatment for 380gallons of water.

– Put a small amount of powder into water and make sure its mixed well.

– Now you place the infected coral or newly purchased coral into the container and leave for 6 hours.

– After six hours has elapsed gently shake the coral in the water to remove dead or dying red bugs and place it into (ideally) your quarantine tank.

Cont’d• In tank treatment1. Calculate total water volume of your tank and all equipment.2. Need to catch all shrimp, hermit crabs as the medication will kill most of

them unless they are very large. Move them to another tank.3. 1 pill = 380gallons of treatment, its always better to go a little over on

your estimate of gallons in your system. Crush the pill(s) into a powder and mix in a cup with your tank water until absorbed.

4. Turn off skimmer, UV, Carbon, phosban reactors5. Pour cup of medicine into the tank and wait 6 hours6. End of 6 hours turn on skimmer, UV, add fresh carbon, phosban

reactors7. You can perform a large water change but is not necessary as the

medication should go neutral after 24hrs8. Ideally you should re-treat 7 days later and again another 7 days later to

make sure you have killed all the possible eggs which could have been missed and hatched between treatments.

9. Once you have finished treating the tank you can re-introduce the shrimp and hermit crabs back into the tank.

• Possible Predators– Wrasses- will not completely kill all red bugs but will help to control

population– Mandarins- This is not a guarantee but some have seen them eat them

Acro Eating Flatworms

• Commonly called AEFW

Identification

• White marks on Acro’s (bite marks)

• Small Orange/brown eggs at base or on coral

• Loss of color

• Tissue recession from their base

• Loss of growth

Consequences

• If left unchecked could cause total death of coral.

Bite marks, Photo from Melev’s Reef

• no in-tank treatment at this time• separate quarantine tank

– Make sure this tank is well cycled and conditioned and is appropriate for housing Acropora corals – The corals can be treated and then placed immediately back into the display tank. Though not

ideal (keeping them isolated in a quarantine tank is ideal)• Dips

– Fresh water dips work but are very harsh on coral– Tropic Marin Pro Coral Cure(TMPCC) dips for 25 to 30min’s.– levamisole hydrochloride

Formula:          Volume in Liters x PPM /mg/ml of drug

For instance: most Levamisole drugs are either 80% or 90% active ingredients. For a 40ppm dose of 90% active Levamisole in a 5-gallon dip, the formula would be: 5gal x 3.78L=18.9L 18.9L x 40ppm/900mg= .84g of Levamisole.The 900mg comes from the active ingredient of the drug. If it’s 100% active, it’s 1000mg/g. Anything less than 100% active is a percentage of that. So a 90% active drug is 900mg/g, an 80% active drug is 800mg/g and so forth.

Dip length is dependant upon users discretion anything from 10 to 30min’s• After Dip

– take a small power head and blow all the coral’s crevices and branches to dislodge any stubborn flatworms. While doing this, carefully inspect the coral for any sign of eggs. If you see small brown egg sacs, either cut off the area, or scrape these eggs off of the coral. Sometimes it is best to cut off all the dead parts of the coral, leaving a healthy, flatworm- free coral.

– Ideally place the coral in a separate Quarantine tank and watch for up to 6 weeks

Treatment of AEFWParaphrased from Reefkeeping Magazine

Montipora Eating Nudibranchs

Identification• White frilly nudibranchs about max of 3mm

in size.

• If you see death on Montipora species coral that is in a band pattern it is most likely them

4 Days later

7 days before was healthy

Consequencesparaphrased from qualitymarnine article

• asexual reproduction (only takes one to make tons)

• A single adult can lay over 100 eggs, they only take a few days to hatch as they have already been incubating within the adult before being laid.  The larvae start out very small, but within the first few days with an abundant food source present they grow quickly, reaching adult size in less than a week after hatching

• If left untreated they will eradicate all montipora species in the tank

Treatment of Montipora eating Nudi’sTreatment Options (as indicated by QualityMarine Article) • Chemical Dips: • These options offer different ways to kill the adult specimens of

nudibranchs.  Eggs are unfortunately resistant to these treatments however it may reduce the successful hatch rate. Eggs must be either removed manually, if they can be found, or allowed to hatch to be treated as adults.  The key is to eradicate any adults before they get a chance to lay eggs.  It is also best to dip all Montipora and Anacropora all at the same time as well as rocks in close proximity to the infected corals, as the nudibranchs are known to frequently roam around in search of new host coral. – Iodine/derivatives – (ex. lugols iodine, TMPCC, Seachem reef dip) when used

at recommended dosages and times, these medications will kill most if not all adults.  Throughout the procedure it is important to stir the coral in an effort to detach any adults from the coral.   Once the dip is complete, the coral should be inspected for any nudibranch remnants which can be removed using a toothpick.

   

– Another option for chemical dips is Levamisole, It acts as a contact poison blocking nerve transmission to kill or stun the parasite. This drug has proven to be a very effective treatment for both parasitic nudibranchs and flatworms.  We recommend a minimum dosage of 50ppm for a total duration of 10 hours or more. At this dosage the nudibranchs become paralyzed and fall off the coral.  This treatment can be used in an existing reef system, however it is advised that it be administered in a separate tank, as there can be a lot of secondary die off of aquatic life.  Note, Levamisole is only available with a prescription from a licensed Veterinarian.

 – Freshwater dipping is a very dangerous yet very effective treatment

option. Freshwater creates a large difference in osmotic pressure between the inside and outside of the body of the nudibranchs. This sudden change in osmotic pressure causes the cells to rupture and quickly kills the nudibranch. The dip must be done with de-chlorinated water adjusted to the pH and temperature of the tank and must last no longer than 15 seconds. Note, this is not recommended as a safe treatment option as it can be very harmful to the zooxanthellae in the coral, longer exposure times can and will kill coral.

Manual removal of adults and egg masses:  • This method is very effective for aquarists with smaller colonies and the

ability to remove those colonies/fragments from the water.  Colonies with deep inaccessible crevices may need to be broken apart in order to provide access to all areas of the coral.  With good eyes and careful observance, these pests can be eradicated within a matter of weeks, as their egg cycle time is less than a couple weeks in length.  Nudibranchs can either be scooped up with tweezers but scraping/squishing their body with a toothpick will also work.  Just be sure to either shake the dead nudibranchs off in a separate container of water or use a jet of water from a pipette or baster to remove any remaining parts. 

 • Introduction of natural predators. • Fish such as certain members of the Pseudocheilinus (Sixline wrasses),

Coris (Coris wrasses), and certain Thalassoma (Banana wrasses) Genus’ are known to actively feed on these nudibranchs.  While this can be an effective control mechanism, it may not completely get rid of all nudibranchs.  Most of these wrasses lack the mobility to get to most of the places where the nudibranchs hide.  There are many other natural predators, including certain crabs, several other nudibranchs, and perhaps more, however these are not as commonly available to the aquarist as the aforementioned fish.

Zoanthid Eating Nudibranchs

Identification• Zoanthid will stop opening

• Loss of Zoanthid polyps

• As they digest the Zoa’s they turn the color of the Zoa’s so its harder to find them

Consequences• Asexual reproduction

• If left unchecked will consume all polyps

Treatment of Zoa eating Nudi’s

• Fresh water treatments are most common

• Also see treatment of Montipora Nudi’s

Acoel Worms

Common name is Red planaria

Identification

• Red/pink/brown/orange flatworms

• 1mm to 3mm in size

• Usually cover substrate and can cover corals

Consequences

• They can reproduce asexual therefore can reach plague proportions very fast

• If left unchecked they can smother coral and cause coral to slowly die

• They are very toxic and once in plague proportions if food runs out there can be a massive die off which can kill fish and invertebrates.

Treatment of Acoel worms

• Siphoning them out of the tank • Fresh water dip corals to get them off• Flatworm exit will kill them but you need to

siphon as much of them out as possible and follow directions on the box to ensure your livestock doesn’t die from the toxins.

• Chelidonura varians slug feeds primarily on them but once flatworms are gone it will die.

Chelidonura varians

Sources• Distressed Clam: http://reefkeeping.com/issues/2008-02/nftt/index.php• Red Bugs: http://www.melevsreef.com/redbugs.html• Red Bugs: http://www.dfwmas.org/Forums/viewtopic.php?t=14402• AEFW: http://reefkeeping.com/issues/2007-09/mc/index.php• AEFW Photos and info also from Joseph Weatherson • Montipora Eating Nudis: http://reefkeeping.com/issues/2007-09/eb/index.php• Montipora Eating Nudis: http://www.qualitymarineusa.com/article.asp?

page=feature&id=FA22AE9A-A335-4F27-A5C5-0913F83DCB60• Pests: http://reefkeeping.com/issues/2004-10/sp/feature/index.php• Red flatworms: http://www.advancedaquarist.com/issues/may2002/short.htm• Acoel worms: http://www.ronshimek.com/Animal%20Groups%202a

%20Flatworms.htm