Brine Shrimp Cysts & Hydroids

[Jerry Gunn]

I have read copious amounts of books and literature on Dwarf Seahorses and brine shrimp (Artemia) where some authors say hydroids can sometimes be introduced into our tanks from brine shrimp cysts. I have always questioned this belief due to the different environments where they exist and breed. I’m sure hydroids would have difficulty surviving in the hyper-saline lakes common to brine shrimp sources. I have asked about this on a couple of other forums where the view was mixed. One responder said he could find no evidence of a dry form of hydroid. A few days ago I decided to ask the worldwide Hydrozoan Society https://www.hydrozoa.org/ if there was any possibility that Artemia cysts could carry the hydroids to our aquariums. I just got this response from an officer of the society: “It is impossible for hydroids to come from Artemia cysts. I agree that snails and macro-algae are the source”. Of course it is very true that hydroids consume Artemia, so an explosion in hydroids will happen with this almost unlimited food source if there are any hydroids in our tanks. Most hobbyists have multiple tanks with several species of algae, snails, crabs and other fish, so cross contamination is likely the culprit. Personally I have no aquariums which contain anything other than Dwarf seahorses and I have never had hydroids. I did get a couple small anemone larvae with my last batch of captive bred Dwarf seahorses. They grew to about 1cm before I noticed them. So even captive bred seahorse sources can introduce freeloaders into our tanks!

 

[Big G]

Great info! Thanks for posting

 

[Henn]

I have read copious amounts of books and literature on Dwarf Seahorses and brine shrimp (Artemia) where some authors say hydroids can sometimes be introduced into our tanks from brine shrimp cysts. I have always questioned this belief due to the different environments where they exist and breed. I’m sure hydroids would have difficulty surviving in the hyper-saline lakes common to brine shrimp sources. I have asked about this on a couple of other forums where the view was mixed. One responder said he could find no evidence of a dry form of hydroid. A few days ago I decided to ask the worldwide Hydrozoan Society https://www.hydrozoa.org/ if there was any possibility that Artemia cysts could carry the hydroids to our aquariums. I just got this response from an officer of the society: “It is impossible for hydroids to come from Artemia cysts. I agree that snails and macro-algae are the source”. Of course it is very true that hydroids consume Artemia, so an explosion in hydroids will happen with this almost unlimited food source if there are any hydroids in our tanks. Most hobbyists have multiple tanks with several species of algae, snails, crabs and other fish, so cross contamination is likely the culprit. Personally I have no aquariums which contain anything other than Dwarf seahorses and I have never had hydroids. I did get a couple small anemone larvae with my last batch of captive bred Dwarf seahorses. They grew to about 1cm before I noticed them. So even captive bred seahorse sources can introduce freeloaders into our tanks!

Hi there, as a Dwarf Seahorse Breeder ( see threads and photos ) there are some common issues here that really need clarity. Every Brine Shrimp egg has a whole eco system riding along. The ( shell ) is not a shell at all. It is a horny callus that is not breakable or digestible. I have lost full size ponies to a single ingestion of these calluses. The outside of the callus is home to every life form required by a brine shrimp ( in the cracks ). There are small Pink Puff Hydras that cause sores that do not heal. The delay in hatching is on purpose. It allows time for the fungus, algae, and plankton that the brine shrimp eats. Without that natural system the hatched brine shrimp would not have a sure food supply. Every breeder washes the eggs to remove the riders. In the end the only way to feed seahorses is to grow a natural forage pasture on mesh. The mesh also keeps the clean up crew from bothering the ponies. Last check there were around 60 ponies in two different marine ponds. They are very happy and they would have no idea what a brine shrimp was. Keep in mind that a pony fry has a mouth that is smaller than a brine shrimp and an adult has a mouth that is 10 times a brine shrimp. They can be moved to a display tank and rotated back outside.

 

[rayjay]

Based on my experience, there is a lot of misinformation here.
It's NOT that the artemia cysts are introducing the hydroids, it's the fact they thrive on the nauplii that are fed to dwarfs and fry of standard seahorses. The hydroids are introduced via non sterilized things added to the tanks they end up in.
If you start with a dwarf tank completely sterilized, and NEVER introduce anything non sterile, the hydroids are not going to appear. However, introducing live rock, macro and corals ARE sources that will introduce the hydroids.
Also, the description of the artemia cyst leaves a lot to be desired. I've never seen cracks on the cysts but they do have a "shrunken appearance until hydrated.
When incubated in seawater the biconcave cyst swells up and becomes spherical within 1 to 2 h. After 12 to 20 h hydration, the cyst shell (including the outer cuticular membrane) bursts (= breaking stage) and the embryo surrounded by the hatching membrane becomes visible. The embryo then leaves the shell completely and hangs underneath the empty shell (the hatching membrane may still be attached to the shell). Through the transparent hatching membrane one can follow the differentiation of the pre-nauplius into the instar I nauplius which starts to move its appendages. Shortly thereafter the hatching membrane breaks open (= hatching) and the free-swimming larva (head first) is born.
The cyst shell consists of three layers:
· alveolar layer: a hard layer consisting of lipoproteins impregnated with chitin and haematin; the haematin concentration determines the color of the shell, i.e. from pale to dark brown. Its main function is to provide protection for the embryo against mechanical disruption and UV radiation. This layer can be completely removed (dissolved) by oxidation treatment with hypochlorite (= cyst decapsulation.
· outer cuticular membrane: protects the embryo from penetration by molecules larger than the CO2 molecule (= multilayer membrane with very special filter function; acts as a permeability barrier).
· embryonic cuticle: a transparent and highly elastic layer separated from the embryo by the inner cuticular membrane (develops into the hatching membrane during hatching incubation).
The thing artemia cysts are known for is the contaminants that adhere to the cyst surface, the most problematic being bacteria like the vibrio species, but many others as well.
A major problem in the early rearing of marine fish and shrimp is the susceptibility of the larvae to microbial infections. It is believed that the live food can be an important source of potentially pathogenic bacteria, which are easily transferred through the food chain to the predator larvae. Vibrio sp. constitute the main bacterial flora in Artemia cyst hatching solutions. Most Vibrio are opportunistic bacteria which can cause disease/mortality outbreaks in larval rearing, especially when fish are stressed or not reared under optimal conditions. As shown on Fig. 4.2.5., Artemia cyst shells may be loaded with bacteria, fungi, and even contaminated with organic impurities; bacterial contamination in the hatching medium can reach numbers of more than 107 CFU.ml-1 (= colony forming units). At high cyst densities and high incubation temperatures during hatching, bacterial development (e.g. on the released glycerol) can be considerable and hatching solutions may become turbid, which may also result in reduced hatching yields. Therefore, if no commercially disinfected cysts are used, it is recommended to apply routinely a disinfection procedure by using hypochlorite (see worksheet 4.2.3.). This treatment, however, may not kill all germs present in the alveolar and cortical layer of the outer shell. Complete sterilization can be achieved through cyst decapsulation.
Now, as for nauplii size, there are some fry unable to consume the newly hatched (actually should be enriched Instar II nauplii) artemia, usually the pelagic seahorses, dwarf fry and most benthic fry of standard seahorses have NO problem ingesting the nauplii.
If you are REALLY interested in artemia, the best authority for them IMO is here: http://www.fao.org/3/W3732E/w3732e0m.htm#4.1. Introduction, biology and ecology of Artemia The italicized parts above came from this document.
If you want to see what cysts really look like, google gives us: https://www.google.com/search?q=microscopic+view+of+artemia+cyst&tbm=isch&source=iu&ictx=1&fir=f5YfdYU-oO5EMM%3A%2C367WHck-a_WqeM%2C_&vet=1&usg=AI4_-kT95zlB2e5Tsy8RSYvpd6lM5zddKQ&sa=X&ved=2ahUKEwjeiPjSmcrpAhVOMt8KHXirDQgQ9QEwCnoECAoQBQ#imgrc=f5YfdYU-oO5EMM:

 

[Henn]

I don't have time to read all your quotes. Since one Gummy Husk has killed several of my seahorses all the data means nothing if One Husk gets through. There is no way to provide a full diet to seahorses ( across their lives ) with Brine Shrimp. Every breeder that uses brine shrimp fails. We ran a 10 gallon habitat just for Brine Shrimp. Because of the rumor that they give husk-less births and the population would contain all sizes. Well, after a year all on their own, some were over an inch long. Great feathery things and babies. The natural habit of free living Brine Shrimp was to maintain a population that would not feed my mandarin goby for a day. The only reason the Brine Shrimp are useful is that there are tons of the eggs in wind rows. Even if a tank starts clean there are no Clean Up crews that are safe for seahorses except Lettuce Nudibranches ( yes we breed them ). Without any Clean Up Crew the tank always goes bad no matter how the bad stuff gets in. There are no pre-hatched brine shrimp that are not contaminated with husks. What is no problem for fish will kill seahorses within hours. People must understand the difference. An Arctic Pod has a real shell ( bright red ). Seahorses hate Arctic Pods because they must suck it in, somehow break the shell, then spit it out in a tiny spray to red shell fragments. They can break up a real shell. Most natural seahorse food has internal micro shells. They can handle this. When they suck in a horny leather like Dog Chew, they can not spit it out. They show great distress and die. After breeding many generations of Dwarf Seahorses it has become clear that some published sources don't even know the correct range of Fry per average birth ( 3 - 7 and it does not matter what is published ). That seahorses are the shortest lived fish in the aquarium trade ( 21 months max on natural forage ). Oldest pregnancy ( 18 months 3 fry ). Tallest male ( 1 3/4 inches curled ). Seahorses do not mate for life ( maximum mates per big male 3 ). No seahorse will approach a dead seahorse within a tennis ball distance ( it does not get the right signs ). In a tank a mated seahorse will wait for it's dead mate to give the right sign, until it starves because in the wild the body would be gone in minutes. What is happening in the marine ponds is real. What we see here is what these creatures do for real. This is not a cut and paste or a rehash of every failed seahorse breeding concept. This not another instant Seahorse Website. If you want to host seahorses, they are social animals. They only live a little longer that a Praying Mantis. Without the survival of the Fry, nothing has been accomplished. How much can someone learn about bees with a hive of one? Sharing real knowledge is my only goal in joining this R2R Community. These ponies have told me what they need by example and it is one heck of allot more than they are getting. Only one Dwarf Seahorse ( LFS fact ) out of 1000 sold will be alive in 6 months. There are 60 out back Courting and Sparking and I didn't start with 60,000. Do whatever you want but until you have at least 4 generations on hand, please consider that my work is based on learning from others and rejecting patent nonsense. I can only advise the same policy for you.

 

[Jerry Gunn]

Based on my experience, there is a lot of misinformation here.
It's NOT that the artemia cysts are introducing the hydroids, it's the fact they thrive on the nauplii that are fed to dwarfs and fry of standard seahorses. The hydroids are introduced via non sterilized things added to the tanks they end up in.
If you start with a dwarf tank completely sterilized, and NEVER introduce anything non sterile, the hydroids are not going to appear. However, introducing live rock, macro and corals ARE sources that will introduce the hydroids.
Also, the description of the artemia cyst leaves a lot to be desired. I've never seen cracks on the cysts but they do have a "shrunken appearance until hydrated.
When incubated in seawater the biconcave cyst swells up and becomes spherical within 1 to 2 h. After 12 to 20 h hydration, the cyst shell (including the outer cuticular membrane) bursts (= breaking stage) and the embryo surrounded by the hatching membrane becomes visible. The embryo then leaves the shell completely and hangs underneath the empty shell (the hatching membrane may still be attached to the shell). Through the transparent hatching membrane one can follow the differentiation of the pre-nauplius into the instar I nauplius which starts to move its appendages. Shortly thereafter the hatching membrane breaks open (= hatching) and the free-swimming larva (head first) is born.
The cyst shell consists of three layers:
· alveolar layer: a hard layer consisting of lipoproteins impregnated with chitin and haematin; the haematin concentration determines the color of the shell, i.e. from pale to dark brown. Its main function is to provide protection for the embryo against mechanical disruption and UV radiation. This layer can be completely removed (dissolved) by oxidation treatment with hypochlorite (= cyst decapsulation.
· outer cuticular membrane: protects the embryo from penetration by molecules larger than the CO2 molecule (= multilayer membrane with very special filter function; acts as a permeability barrier).
· embryonic cuticle: a transparent and highly elastic layer separated from the embryo by the inner cuticular membrane (develops into the hatching membrane during hatching incubation).
The thing artemia cysts are known for is the contaminants that adhere to the cyst surface, the most problematic being bacteria like the vibrio species, but many others as well.
A major problem in the early rearing of marine fish and shrimp is the susceptibility of the larvae to microbial infections. It is believed that the live food can be an important source of potentially pathogenic bacteria, which are easily transferred through the food chain to the predator larvae. Vibrio sp. constitute the main bacterial flora in Artemia cyst hatching solutions. Most Vibrio are opportunistic bacteria which can cause disease/mortality outbreaks in larval rearing, especially when fish are stressed or not reared under optimal conditions. As shown on Fig. 4.2.5., Artemia cyst shells may be loaded with bacteria, fungi, and even contaminated with organic impurities; bacterial contamination in the hatching medium can reach numbers of more than 107 CFU.ml-1 (= colony forming units). At high cyst densities and high incubation temperatures during hatching, bacterial development (e.g. on the released glycerol) can be considerable and hatching solutions may become turbid, which may also result in reduced hatching yields. Therefore, if no commercially disinfected cysts are used, it is recommended to apply routinely a disinfection procedure by using hypochlorite (see worksheet 4.2.3.). This treatment, however, may not kill all germs present in the alveolar and cortical layer of the outer shell. Complete sterilization can be achieved through cyst decapsulation.
Now, as for nauplii size, there are some fry unable to consume the newly hatched (actually should be enriched Instar II nauplii) artemia, usually the pelagic seahorses, dwarf fry and most benthic fry of standard seahorses have NO problem ingesting the nauplii.
If you are REALLY interested in artemia, the best authority for them IMO is here: http://www.fao.org/3/W3732E/w3732e0m.htm#4.1. Introduction, biology and ecology of Artemia The italicized parts above came from this document.
If you want to see what cysts really look like, google gives us: https://www.google.com/search?q=microscopic+view+of+artemia+cyst&tbm=isch&source=iu&ictx=1&fir=f5YfdYU-oO5EMM%3A%2C367WHck-a_WqeM%2C_&vet=1&usg=AI4_-kT95zlB2e5Tsy8RSYvpd6lM5zddKQ&sa=X&ved=2ahUKEwjeiPjSmcrpAhVOMt8KHXirDQgQ9QEwCnoECAoQBQ#imgrc=f5YfdYU-oO5EMM:

Thanks rayjay for the anaylsis which I agree with totally. I have always used the:

Laboratory of Aquaculture and Artemia Reference Center
University of Ghent
Ghent, Belgium

document as my goto for Artemia information.

Jerry

 

[rayjay]

Henn, I have already congratulated you in a post for what you have accomplished as it IS a BIG accomplishment. However, I also have to state when I see you misleading people wanting into the hobby.
I have been in the seahorse keeping hobby for 18 yrs with seven species including dwarfs and the ONLY reason I've stopped breeding and selling seahorses is that I'm now 77 yrs old with disabilities, although I still do keep barbouri and abdominalis.
It's funny you say dwarfs can't be kept on artemia nauplii, but in fact, mine did. I also know that Seahorse source used brine shrimp nauplii as well, and while I haven't asked her, probably Alyssa's Seahorse Savvy does as well. However, with my standard seahorses that produce PELAGIC fry that are smaller than most benthic producers, I did use copepods and enriched rotifers for the first 7-10 days before then going to enriched artemia nauplii.
You mentioned a dwarf that died upon ingesting an artemia shell, and it IS a fact that many marine fish with small digestive tracts have suffered that fate in hobbyist tanks. But, the fact is that when PROPERLY decapped, the residue remaining is soft and WON'T cause blockage, especially as MOST is removed by proper separation procedures for removing the nauplii. Also, even if you DON'T decap, the hard cysts are EXTREMELY unlikely to be eaten by dwarfs, seahorse fry or standard seahorses (although it occasionally MIGHT happen) as their natural instinct is to select live food that they see motion from. Even the standards won't even eat all the frozen food introduced, usually only choosing what they perceive to be proper in their own eyes which is usually the whole pieces and not partial mysis.
While there are MANY failed attempt to keep dwarfs, it is the same for standard seahorses also but again there are SO many that have succeeded using enriched brine shrimp for dwarfs AND for fry of standard seahorses.
Also, consider the marine aquaculture industry where brine shrimp nauplii are used for marine specimens that are even smaller than dwarf fry and are the largest consumers of artemia cysts in the world, Far more than the total hobby industry.
I would agree that it would be a LOT more challenging if one DOESN'T enrich the artemia first, but with proper selection of enrichment type matched to the intended use it is the best working practical solution yet, hobby and commercial.
Lastly, I'd like that when you say "seahorse(s), instead of saying "That seahorses are the shortest lived fish in the aquarium trade" say instead, that "DWARF seahorses are...."
IME, dwarfs can live 1 1/2 to 2 1/2yrs in captivity, and, it is a fact that standard seahorses kept in optimum conditions are likely to live 7-8 yrs and beyond. My oldest ones have been almost 10 yrs and I know that some keepers HAVE gotten to and beyond that point.
To be fair to you, these STANDARD seahorses were weaned off of live brine and onto frozen mysis as a practical move, but if you really want to, you can maintain them with adult brine shrimp enriched properly with an enrichment that includes high DHA levels. Again, this is something that HAS been done, not just talked about.

 

[Jerry Gunn]

rayjay, did you read the PM I sent to you?

Jerry

 

[Henn]

Henn, I have already congratulated you in a post for what you have accomplished as it IS a BIG accomplishment. However, I also have to state when I see you misleading people wanting into the hobby.
I have been in the seahorse keeping hobby for 18 yrs with seven species including dwarfs and the ONLY reason I've stopped breeding and selling seahorses is that I'm now 77 yrs old with disabilities, although I still do keep barbouri and abdominalis.
It's funny you say dwarfs can't be kept on artemia nauplii, but in fact, mine did. I also know that Seahorse source used brine shrimp nauplii as well, and while I haven't asked her, probably Alyssa's Seahorse Savvy does as well. However, with my standard seahorses that produce PELAGIC fry that are smaller than most benthic producers, I did use copepods and enriched rotifers for the first 7-10 days before then going to enriched artemia nauplii.
You mentioned a dwarf that died upon ingesting an artemia shell, and it IS a fact that many marine fish with small digestive tracts have suffered that fate in hobbyist tanks. But, the fact is that when PROPERLY decapped, the residue remaining is soft and WON'T cause blockage, especially as MOST is removed by proper separation procedures for removing the nauplii. Also, even if you DON'T decap, the hard cysts are EXTREMELY unlikely to be eaten by dwarfs, seahorse fry or standard seahorses (although it occasionally MIGHT happen) as their natural instinct is to select live food that they see motion from. Even the standards won't even eat all the frozen food introduced, usually only choosing what they perceive to be proper in their own eyes which is usually the whole pieces and not partial mysis.
While there are MANY failed attempt to keep dwarfs, it is the same for standard seahorses also but again there are SO many that have succeeded using enriched brine shrimp for dwarfs AND for fry of standard seahorses.
Also, consider the marine aquaculture industry where brine shrimp nauplii are used for marine specimens that are even smaller than dwarf fry and are the largest consumers of artemia cysts in the world, Far more than the total hobby industry.
I would agree that it would be a LOT more challenging if one DOESN'T enrich the artemia first, but with proper selection of enrichment type matched to the intended use it is the best working practical solution yet, hobby and commercial.
Lastly, I'd like that when you say "seahorse(s), instead of saying "That seahorses are the shortest lived fish in the aquarium trade" say instead, that "DWARF seahorses are...."
IME, dwarfs can live 1 1/2 to 2 1/2yrs in captivity, and, it is a fact that standard seahorses kept in optimum conditions are likely to live 7-8 yrs and beyond. My oldest ones have been almost 10 yrs and I know that some keepers HAVE gotten to and beyond that point.
To be fair to you, these STANDARD seahorses were weaned off of live brine and onto frozen mysis as a practical move, but if you really want to, you can maintain them with adult brine shrimp enriched properly with an enrichment that includes high DHA levels. Again, this is something that HAS been done, not just talked about.

I do like having input from fellow forum people. With 750 gallons of marine ponds it isn't possible to use something as labor intensive as Brine Shrimp. It often takes up more time than the hobby. Another concern I have is that without extensive knowledge about how to use them, they are not nutritious and they are dangerous. I only ever talk about Dwarf Seahorses. Some people and articles confuse Pygmy with Dwarf. I just do Dwarf and I do not have to supplement at any stage of life. If I was doing Regular Seahorses it would be appropriate to use the Banana Bag. If you try this freebie it may save you some time and energy as well as providing your critters a welcome change.
You will need:
1 nice banana
exacto knife
1 brown paper bag
1 Breeding Colony of flightless fruit flies small size ( Josh's Frogs about $ 16 to make many bananas )
Cut 3 to 5 small holes into the banana on the inside curve
Fill the holes with Fruit Fly Maggot juice from the colony
Cut a corner off the Paper Bag and hang the Banana inside
Hang the Banana Bag over the tank
A constant rain of tasty fruit flies will fall onto the water from the hole in the bag. It never stinks and ends up looking like a dried Carob Bean. Hang a fresh holed banana in the bag to start again. This method doesn't work for dwarfs. The flies are slightly too big. It should work great for you. The thought of bubbling jars or even barrels of Brine Shrimp make me weary to this day. I never know about peoples level. I quit a Forum once when someone asked : I have been cycling my tank now for 6 weeks, When do I add the Salt ???

 

[Jerry Gunn]

rayjay, did you read the PM I sent to you?

Jerry

rayjay, I sent another PM to you concerning your questions.

Jerry