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Thursday, July 14th, 2011

Hydroids are tiny jellyfish-like creatures that infest tanks with low flow, such as seahorse fry tanks and larval rearing vessels. The bad news is, they can sting and kill dwarf seahorses and fish fry that get too close to them. Hydroids love to eat baby brine shrimp and can be introduced to the tank on almost anything, including the shells of brine shrimp eggs.

There are a couple things you can do to prevent contamination of your tank with hydroids. Make sure you are using decapsulated brine shrimp eggs, or decapsulate them yourself. You can buy already decapsulated brine shrimp from

Your best weapon against hydroids is a drug called Fenbendazole (Panacur). However, you should familiarize yourself thoroughly with this drug before using, or better yet, talk to your veterinarian first. Reeftools and its colleagues can not be held responsible for any result of you reading this blog and using Fenbendazole. Personally, I’ve used this drug safely with dwarf seahorses and Fundulus heteroclitus Killifish. I’ve read that it can be safely used with other fish fry such as Clownfish. In low doses it can be safe for clean up crews such as Nassarius snails, cleaner shrimp, and hermit crabs. Be careful and do lots of research before using Fenbendazole.

Any living creatures or plants you want to add to your dwarf seahorse or fry tank should be treated with Fenbendazole first. Keep in mind, most invertebrates and corals DO NOT tolerate Fenbendazole and will die. Macroalgae such as Caulerpa and Chaetomorpha as well as the beneficial nitrifying bacteria in live rock handle treatment with the drug very well. Fenbendazole is by no stretch of the imagination considered to be reef safe. So don’t dose your reef tank with this stuff. Fenbendazole also tends to absorb into glass and rock, leaching into your tank forever. The granules seem to leach worse than the liquid does.

What should you do if you find hydroids in your dwarf seahorse tank or fry tank? Fish seem to tolerate Fenbendazole treatments well. Unfortunately, hydroids don’t even flinch from other common parasite treatments like low salinity, Praziquantel, or formalin baths. So far only Fenbendazole has proven an effective treatment.

Where can you get Fenbendazole? There are plenty of online or local farm animal feed stores that carry it. I use Safe-Guard Fenbendazole/liquid Goat Wormer by Intervet (fenbendazole) Suspension 10% (100 Mg/ml). It’s very important to choose one that is not flavored. Make sure you have done plenty of research and are aware of the risks of using this medication before you proceed. The dosage for fry tanks is 0.2 ml per 10 gallons. Repeat the dosage every other day for a total of three dosages. By the third dose, all hydroids should be dead.

Fenbendazole can also eradicate Aiptasia, bristleworms, and other marine worms.

Wednesday, June 15th, 2011

Yesterday my co-worker Bill noticed an extraordinarily long, but thin, shrimp leg darting in and out of a series of holes that appeared to be drilled through the top of the rock. He chiseled open the rock and found this pistol shrimp. The pistol shrimp had to have been trapped inside the rock unable to leave since it was very young, similar to the way a gall crab grows inside a coral. If anyone recognizes this pistol shrimp and can identify it, please leave a comment.

(Yes, we know the image is huge when you click on it, we wanted to make sure you can see the details)

Thursday, May 12th, 2011

I’m very happy to report that over the last three days, my Hippocampus erectus seahorse named Kohala has given birth to about 26 healthy fry! His mate and the mother of his babies is a Hippocampus angustus named Marmalade. I acquired Marmalade about a year ago as a wild-caught seahorse from West Australia. She was accompanied by five other Aussie wild caught seahorses, as it was my plan to introduce two Aussie species into the captive-bred seahorse market in the U.S. Unfortunately, the divers caught same-sex pairs of three different species. Marmalade is now the only survivor of the Aussies I had imported. She is a jewel of a seahorse, beautiful, friendly, and healthy. I decided to pair her with Kohala, a stunning yellow male H. erectus that I raised from birth.

As far as I know, this is the first time these two species have been hybridized. Honestly, I wasn’t sure if it was even possible, since they are so different. H. erectus is from North America, H. angustus is from the complete opposite side of the world in West Australia. The two species are separated by millions of years of evolution. This is why seahorse taxonomy is so messy. Seahorses laugh in the face of taxonomists, lumpers and splitters alike!

I know hybridization can be a hot-button topic. In general, I don’t agree with creating hybrids. Take hybrid cichlids for example. Two different species with different inherent behaviors and traits crossed together can make some very confused and often deformed hybrids. Releasing invasive hybrids into the wild can wreak havoc on local ecology. Things seem to be a little different in the marine breeding hobby, though. People who own hybrid marine species may be slightly less likely to dump them into their local waterways when they grow too large for their tanks. I don’t look forward to marine fish hybridization becoming as commonplace as it is in the freshwater hobby, but I’ve seen some really cool hybrid clownfish like Sanjay’s Black Photon Clownfish.

I’m curious; what are your thoughts on hybridization in the marine aquarium hobby, readers? Leave us a comment!

Saturday, April 16th, 2011

Don’t miss the NCPARS spring 2011 frag swap at the beautiful Williamsport, PA High School with awesome raffle items from, Jason Fox, MEI Crystal Sea salt, Aquatic Life, Premium Aquatics, Seachem, Avast Marine, DT’s phytoplankton, Hagen, Alga Gen, That Pet Place, Rod’s Food, Frag Farmer, Brightwell, Boston Aquafarms, Hamilton Lighting,, United Pet Group, Reed Mariculture, Marco Rocks, and many more.

Come to the swap to see the shining star of NCPAR’s School Tanks Program in the Williamsport High School. Through this program, NCPARS members help setup and maintain reef aquaria in their local schools. In some cases schools have provided generous financial support for aquarium setup. In others the tanks have been setup through individual donations. In Williamsport, the main tanks include a 300 gallon Marineland Deep Dimension reef and a 125 gallon reef. Two 65 reefs have specialty habitats for venomous fish and angels. Theyalso have two 90 gallon frag tanks and two 15 gallon acclimation tanks.

Thursday, April 14th, 2011

If you’re like me, you’re a big fan of Ken Nedimyer and the Coral Restoration Foundation. If you missed the Delaware Valley Reef Club Spring 2011 frag swap and you still want to see Ken’s keynote speech, you can watch the video provided by DVRC on youtube:

I am a new member of DVRC this year, and I went to this swap representing the fish store I work for, The Hidden Reef in Levittown, PA. We brought frags illuminated by Acan Lights, the new Echotech coral glue, aquacultured live rock, and lots of other goodies for sale. My coworkers and I had a great time at this successful event meeting the members and other sponsors of this great reef club.

Before Ken’s talk about The Coral Restoration Foundation, Barb Lang gave a talk about Clownfish breeding, and I gave a talk about aquarium photography. You can also watch these videos on Delaware Valley Reef Club’s Youtube page.

DVRC has volunteered to sponsor a section of The Coral Restoration Foundation’s reef where they grow rare Elkhorn and Staghorn Acropora corals. The CRF is saving the reef, one frag at a time, and you can be a part of it. Send donations to, and DVRC will donate $0.50 for each $1.00 you donate! You can read more on the donation thread here.

Wednesday, April 6th, 2011

The Gobiesox Clingfish larvae I’ve been raising started settling at 25 days and have now completed metamorphosis. They look like exact replicas of their parents now, fins and all. It’s easy to tell when Clingfish settle because they start clinging to surfaces rather than free swimming (I’m now almost certain of their species, since it takes longer for Gobiesox punctulatus to settle than G. strumosus). They have been growing faster and eating more than ever since settling and are now about 3/4″ long. They are expert live Tigriopus copepods hunters; soon I will start giving them a little bit of Cyclop eeze, which is a great transition food for small fry.

I apologize for the grainy settlement photos, I’m not taking macro shots of them anymore since it’s too difficult to pry them off the walls without stressing them. It was much easier when they were free swimming, and I could quickly catch and photograph them before they even knew what was happening. I want to make sure they grow up happy and healthy.

development photos:

Eggs and parents

4 and 7 days old

10 and 15 days old

23 days old almost settled

Monday, March 21st, 2011

The Gobiesox Clingfish larvae I’ve been raising are 24 days old today. I only have 13 left, and some of those are very stunted. There are about five really healthy, large ones that are doing great. They have been eating enriched 2 day old brine shrimp since they were 7 days old, but I am still putting rotifers in for the smaller fry. The majority of this batch was lost in the beginning when my rotifer culture crashed and I was forced to give them baby brine shrimp. My rotifer culture is doing great now, but I’m afraid it’s too little too late.

They’ve had noticeable pectoral and tail fins since at least day 7, but dorsal and anal fins didn’t show up until around day 15. All the fins are now clearly visible, and these larvae are starting to look more like fish. I believe this species is Gobiesox punctulatus, which starts going through metamorphosis around 20 – 25 days. The larger larvae are spending more time being horizontal to the sides of their container; it’s only a matter of time before they start clinging and stop being larvae!

development pictures:

4 and 7 days old

10 and 15 days old

Tuesday, March 15th, 2011

My Gobiesox Clingfish larvae turned 15 days old on Saturday. After my rotifer culture crashed, I raised them on mostly newly hatched decapsulated baby brine shrimp and a few copepods. They’ve been eating enriched 2 day old brine shrimp for a few days now, and their growth is really obvious! I’m enriching the brine shrimp in a hatching cone for 24 hours (two 12 hour periods with water change/new enrichment additon between), alternating with Dan’s Feed from and Selco. I also add Nannochloropsis Algae paste to the water to help the fry see their food and not constantly bang their heads on the walls. Nano paste also helps keep the brine shrimp nutritional values higher. Click here to see last week’s 7 day update.

Monday, March 7th, 2011

Always check new corals for coral eating nudibranchs and slugs. Many people are familiar with the Zoanthid eating nudibranchs, but there are nudibranchs and slugs that eat all types of corals. These pests are well camouflaged and not easy to spot, preferring to hide at the base of their hosts. Look for them around receding tissue, polyps that won’t open, or dead white skeleton. It is strongly recommended to quarantine new corals and to dip them in a coral dip, flatworm exit, or iodine before placing them in the tank.

Tritonia spp. nudibranchs are often seen on purple Gorgonians from the Caribbean and can do serious damage in a short time if not removed. Unfortunately, they are extremely tiny and transparent. LPS eating slugs like the Turbinaria eating slug and Scolymia eating slug are not particularly common, but they show up from time to time. Removal is not difficult since they are relatively large and don’t seem to reproduce in captivity. Phestilla melanobrachia is a nudibranch that eats Dendrophyllid corals and grows up to 2 inches in length. They are usually found on Tubastrea spp. corals in captivity. Small Zoanthid eating nudibranchs are fairly common on almost types of Zoanthids. There are countless other species of slugs and nudibranchs that eat other corals like Xenia, tree corals, Montipora, etc.

Anatomy of an Aeolid Nudibranch

Zoanthid eating nudibranchs and Tubastrea eating nudibranchs are both types of Aeolid nudibranch. The black specks behind the first two antennae are the eyes. The finger-like appendages on the back are called cerata. The darker tips of the cerata are called cnidosacs. A Zoa eating nudibranch can consume immature nematocysts from its prey and store them in these sacs for protection against predators. The nudibranch also gets its coloration from its prey. Like their cousins the photosynthetic Elysia spp. slugs, Zoanthus eating nudibranchs even steal zooxanthellae from the Zoanthus.

Reefers have had success eradicating the Zoa eating nudibranch with Salifert’s Flatworm Exit in high doses. Obviously, you have to be careful using this method. It’s best to take affected colonies out of the tank and treat them in a bucket of tank water with an overdose of Flatworm Exit. If you have a lot of hidden planaria (which release toxins when they die) in your main tank, it could crash. Have several pounds of carbon on hand when using Flatworm Exit. Since Flatworm Exit won’t kill the eggs of the nudibranch, you need to repeat the treatment four days later. These treatments may work on other types of coral eating nudibranchs and slugs.

Friday, March 4th, 2011

Last Friday I brought home some Clingfish larvae from work (The Hidden Reef in Levittown, PA), probably Gobiesox punctulatus. Of course, my rotifer culture that I’ve had for months crashed without warning as they are likely to do in the hands of busy people, and I was worried I would lose all my Gobiesox larvae. I’ve been giving them newly hatched, decapsulated Artemia (baby brine shrimp) every 12 hours, siphoning out the uneaten, older artemia first. I add DT’s Phytoplankton to the fry bucket as often as I need to tinge the water green. This helps the fry see their prey and keeps the Artemia nutritional profile higher. I have about 40 out of 100 Clingfish larvae left, and about 15 are obviously larger and have more dark pigment than all the others.

I just got some Moina salina and more rotifers from today. I’m going to give both to the larvae and see if the smaller ones start to catch up in growth to their bigger siblings.

Here are some photos of a 4 day old Clingfish larva with Artemia in its gut, and 2 photos of a 7 day old Clingfish with Artemia in its gut. The first is a side on view, and the second is a shot of the underside of the larva. Stay tuned to for more updates!

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