Best First Food For H.Erectus Fry

[dmcmares24]

What is the best first food for H.Erectus Fry and where can I purchase it online? I just cant keep them alive with the newly hatched brine schrimp.They are dying off in a matter of 2 weeks.Is it rotifers or copepods? Can I keep the cultures living for a extended period of time? Any:headwally: help would be appreciated. Thanks.

[vlangel]

What is the best first food for H.Erectus Fry and where can I purchase it online? I just cant keep them alive with the newly hatched brine schrimp.They are dying off in a matter of 2 weeks.Is it rotifers or copepods? Can I keep the cultures living for a extended period of time? Any:headwally: help would be appreciated. Thanks.
Are you sure the food is the reason they are dying off? Maybe they are succumbing to bacteria?
Do you see them snicking the baby brine shrimp. If they are eating it at first then stop eating it, it might be bacteria in their gut. I lost some to that when I was enriching the bb shrimp with selcon. When I switched to only Dan's Feed then I stopped losing fry.

[rayjay]

Are you decapping the cysts before hatching? Do you use peroxide on the brine nauplii before feeding them to the fry nursery?
Are you ongrowing the nauplii for a day and then enriching them? What enrichment?
Do you remove uneaten food before adding a new feeding?
How often are you cleaning the fry container and doing water changes? Are you removing the bacteria slime often by wiping down the sides, bottom and hitching and siphoning out the residue?
Do you check for ammonia in the fry container?
Yes, the brine cultures can be grown to their adult stage but many have trouble doing it in any significant densities. However, that is not necessary for the fry in the first two weeks, but it helps to get started right off with ongrowing to adults as it takes some time to do and they can grow as the fry grow.
My Brine Shrimp Page (http://www.angelfire.com/ab/rayjay/brineshrimp.html)
Many feed rotifers in addition to the brine nauplii, and while it is a welcome addition to the nutrient profile, probably the majority of fry are raised without it.

[dmcmares24]

Yes, I was enriching them with Selcon. I have heard about Dans Feed and also a water conditioner for sea horse fry from seahorsesourse.com. I think that I will try both of those things next time. hopefully with better luck. Is it true that the sea horse fry have alot of trouble digesting the freshly hatched brine schrimp?

[dmcmares24]

Yes, I was using the decapped eggs.

[rayjay]

The Instar I stage is supposedly harder to digest and I take Dan Underwoods word for this as he investigates his information extensively.
The Instar I stage also cannot feed as the digestive tract is not complete until they molt to the second Instar. That is why you need to hatch, grow for a day, and then enrich. One 12 hour stage will gut load them, but a second 12 hours with new water and new enrichment will also have the nutrients assimulated into the flesh making them more nutritious.
Dan's Feed IMO is a superior product to the Selco/Selcon emulsions.
The emulsions make it too easy to kill off the brine nauplii when enriching them as it can give an oily smothering coating to the nauplii, and, it definitely doesn't store anywhere near as long as the powders.
The Dan's Feed has to be blended in water first, but while most don't do that with the emulsions, the emulsions would be better if they too were blended into the culture water.
The Algamac 3050 that Dan uses in his mix is a much higher DHA product than even the DHA Selco.
The water conditioner you mention I'm assuming is the Mic F Good bacteria which is added to the tanks to lessen the production of Nasty bacteria.
The health of the adult seahorses is ALSO a factor in viability of their fry.
When I was raising H. reidi fry, I had no luck until I started enriching live adult brine and feeding to the adults once or twice a week.
I guess that the frozen mysis wasn't quite enough for the best of health for the seahorses and after a few months of the enriched live adult brine treatment, I became successful in rearing H. reidi fry.
These are my own personal findings over the years, but others probably have other points of view and hopefully they will chime in here for you.
I almost forgot to mention that if you don't remove the uneaten food, it's not just that the fry will eat enrichmen depleted food, they could also be eating too much of the nauplii so that the nauplii pass through the digestive tract much too fast so that it's not digested properly and they don't get sufficient nutrition, even though the nauplii are enriched. Sometimes you can even see live nauplii coming out the anal opening.

[George_G]

What is the best first food for H.Erectus Fry and where can I purchase it online? I just cant keep them alive with the newly hatched brine schrimp.They are dying off in a matter of 2 weeks.Is it rotifers or copepods? Can I keep the cultures living for a extended period of time? Any:headwally: help would be appreciated. Thanks.

In addition to the good information already posted here, since you are from Long Island, it would behoove you to have a look at Todd Gardner's research paper on precisely what you're asking about.

http://seagrassli.org/ecology/fauna_flora/seahors/ToddGardnerThesis-PDF.pdf

Also, I assume you know there are two "races" of H. erectus, a Southern and a Northern, and each presents different problems in raising the fry. If you are working with our local Long Island ones, Todd's paper is especially apropos.

Good Luck!

George

[dmcmares24]

Thanks George. Todd's paper confirms that the use of copepods for at least the first couple of days will give you a higher survival rate.There are a lot of different vendors selling copepods on the internet, which of them do you feel is a reliable source? From what I have been reading, Seahorsesource.com is one of the best.

[DanU]

Copepods are definitely a superior food when available and appropriately sized. The problem is having enough and having enough the right size. I have clocked fry eating 2 copepods in 30 second intervals. Multiply that out times the number of fry and daylight feeding hours, and you will quickly find, you can't grow enough. One of the commercial producers of copepods tried raising H. reidi since they already produced copepods. They quickly found that production was not enough to feed them copepods exclusively.

The other issue is food mass. Being nutritious is not enough. There has to be enough volume of food. One copepod in the 100 micron range is more nutritious or has a better nutritional profile than a single enriched artemia nauplii but it is many times smaller. 100 microns vs 600 - 800 microns. They have to eat many more copepods to equal the same mass.

As pointed out, knowing the origins of your brood stock is important. Southern erectus fry can easily take enriched artemia nauplii from day one. Done properly, survival rates can exceed 90%. Northern erectus fry on the other hand are smaller and to achieve high survival rates, copepods are needed to start with, at least for the first few days.

Dan

[ThRoewer]

I had seahorse fry that could easily take freshly hatched brine shrimp, though they failed to digest them. I could watch the little seahorse swallowing one, follow how it would pass through the seahorse's intestines and when it was pooped out a minute or two later - and after a second or two continued swimming away as if nothing had happened. It was quite frustrating to watch.

[DanU]

You hear of this happening a lot with newly hatch artemia but not with properly enriched artemia. It appears that after they have molted a time or 2, they become more digestible. According to Robert Browns book Artemia Biology, newly hatched are harder to digest. Apparently they have a harder carapace. Also newly hatched are lacking in several amino acids. This doesn't even get into the nutritional profile deficiencies. Much of this is largely corrected with ongrown that is properly enriched. From a size standpoint, Instar II and III are longer than newly hatched but not any wider. I have found that if the seahorses can take newly hatched, they can take enriched just as well.
Benthic species such as H. erectus, H. barbouri, H. zosterae, H. abdominalis can have very high survival rates, approaching 90% and higher with artemia.
Pelagic species such as Northern H. erectus, H. reidi, H. kuda, H. fisheri, H. ingens, etc. will not fair as well with artemia as a first food and you will have higher survival rates with copepods provided you can get enough and appropriately sized.

Dan

[ThRoewer]

Well, back in the days when I was trying to breed seahorses the teaching was to feed the freshest hatched naupli possible as their shell was supposedly not hardened yet. Had I only known that waiting a day or two while loading them up with nutrient would have improved the digestibility and nutrition for the seahorse fry...

[RedAnt78]

This might be at least part of the problems I've been having, I had been feeding freshly hatched and and like 12-24hr old bb so really they weren't "digestible" and really weren't even enriched!

[rayjay]

While it might be the problem, there are others who have succeeded when feeding as you have been, and many who ongrow and enrich the artemia first, and still have problems.
Keep making improvements and sooner or later you will get it.
I first started with raising H. reidi fry and it took me until my tenth batch to succeed.

[RedAnt78]

Thanks for the feedback, I'm gonna keep trying to get it right!