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The above pictures are taken by Mr. Hisaya Suzuki, a Japanese breeder specializing in rare ``mutant'' colors of the shrimp that we know as Caridina.

Caridina Serrata information

Mr Hisaya Suzuki about his Bee shrimp

On Mr. Hisaya Suzuki's Japanese Bee Shrimp homepage (now off line) I read how to take care of these Japanese shrimp (he himself breeds a variety, the Crystal Red).:

"If you are beginner of your aquarium life, it is a little difficult for you to keep them alive. If you already keep plants in your aquarium, you can keep the shrimps healthy. NO ammonia in the tank. It is fatal for them.
They need pure & clean water. Normal bee shrimps are tough, but Crystal Red Shrimps are very sensitive.
PH 6.2--7.2 and temp 22--25 degrees celcius
PH 7.5 or over is dangerous for bee shrimps.
Filtration is necessary. I use charcoal & carbon filter material.
"EHEIM" style filter is recommended, but I'm now using upper flow filter for my 12 gal (45 liter) tank, with no problem.
Chemicals are not good for them.
Their life span is about 15 months. They're adults in 6 months. An adult Crystal Red spawns 20-30 babies monthly.
If you find eggs under their bodies, you will see babies after 3 weeks.
They may eat algae, but other food is recommended for them.
Fantinalis antipyretica/Riccia fluitans (a kind of moss) are good for them. Boiled spinach is their favorite.
As soon as you put spinach in your tank, they will come to eat it.
You may treat to them one or two spinach every 3 days.
If they ignore spinach, It is a time to change water. (Bad water conditions)"

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Mr W.A. Tomey about the "master nibblers" in our tanks

Summarized and translated by Jochem 't Hoen (with additions by Jochem and Frans Goddijn) from an original article in the Dutch publication "Het Aquarium" Algae-masters in our tanks

When Tomey first kept these shrimp, he discovered how they terminated a plague of beard-algae in a very short period. He decided to study them more closely and started a little experiment. He bought some Crypto's that were severely suffering from the algae on their leaves. He placed them in his tank and almost immediately the shrimp came forward, and began to pull and eat the algae. Only twelve hours later the leaves were clean again and looked like the algae had never been there.

This is a story that most people in Holland can't accept. They just think it is impossible and don't want to discuss the matter any further. I think that it's a shame, because it is a magnificent sight to see how the shrimp use their legs/scissors to pick up their food and bring it to their mouths. I also have doubts on the speed they can develop, but I'm sure they'll eat the algae.

Caridina shrimp are 3 to 5 cm in size and can be found from Africa via Pakistan, China and Malaysia as far as New-Guinea and Queensland in Australia. In China three new species have been described only recently.

Many local forms and colors exist.

Tomey first didn't know which of the 120 Caridina-species he kept, but a visit to Drs. C.H.J.M. Fransen of the Rijksmuseum voor Natuurlijke Historie in Leiden, the Netherlands sufficed to find out he was dealing with Caridina serrata "Stimpson" 1860, a miniature prawn. This shrimp has been imported from Hong Kong where several sweet water shrimp hail from, like Macrobrachium nipponense "De Haan", Macrobrachium formosense 'bate", macrobrachium hainanense "Parisi", Caridina lanceifrons 'Yu", Neocaridina serrate "Stimpson" and caridina Serrata "Stimpson".

The latter species live in high brooks and rivulets within the Lam Tsuen river system in the New Territories of Hong Kong.

A shrimp that, according to Tomey, like all FW-shrimp is living on dead organic matter and algae. In our tanks they also accept dry food tablets.

The shrimp are caught in the plants that are hanging from the river-banks into the water in Asia. The small rivers they live in are not deeper then 50 cm, and have a sandy substrate covered with stones of all sizes and are loaded with plants.

Caridina are caught by dragging a strong net through the plants close to the embankment of the stream. Caridina can be caught in all seasons but the populations are large in summer and small in winter, even when the temperature doesn't differ that much.

pH 6,8-6,9
O2 > 0,08 mg/l
T 18-28 degrees Celsius

We must keep these shrimp in a tank that is NOT too clean, and thus contains enough organic matter for the shrimp to eat, planted with a lot of moss-like plants. Under these circumstances we can expect to see a lot of these shrimp in our tanks. 200-500 specimen in a small tank are no exception!

The females lay about 7-23 eggs between their swimming-legs, which will develop in about 28-33 days. The fry is released as soon as they leave the eggs and so the shrimp are in their way live bearing. The smallest fry already strongly resemble the adult shrimp when they are born. Then they will need a lot of finely spun plant material, like aquatic moss in order to escape from predators. In about 7 months they'll reach adult size and be ready to reproduce.

The young shrimp shed their skin 13 times while they grow. An adult female can have eggs, an adult male has different swimming legs. The eggs are large and brownish pink in hue. The number of eggs can be any between 7 and 23. In the wild, breeding seasons can differ considerably. In the subtropics (like Hong Kong) breeding is consigned to the warm season, 18 to 20 degrees celcius. In a heated tank Caridina can have eggs all year round. A temporary peak in egg production can be triggered with a higher temperature and a sufficient supply of extra food to induce mating.


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Notes from my logs

The following information is taken from logs entries to my tank diary: Caridina serrata, Japanese bee shrimp
A month after starting the tank, I added 11 specimen of the small Japanese Bee Shrimp = Caridina serrata to my tank. Well, it's probably a subspecies but I haven't figured out yet which.
I also have a group of similar shrimp, about the same size and body shape but grayish brown, mostly transparant, some of these have an opaque white/creamy stripe from head to tail. The latin name seems to be Aeolicus strigatus (which is what the import firm's form said...

The interesting aspect about these guys is that most of them hide themselves and only a few of them don't care about being seen at all. In my observation it is so that in a properly planted tank (lots of plants, plenty good hiding places) when you are able to see 3 of these shrimp, you can be sure that there are actually 11 in them (i.e. in my tank).
In the tank they are coming from, also a good, densely planted tank with healthy plants, it's easy to count 15 of them but in fact (when studied and counted methodically and painstakingly) there are almost 300 shrimp. So the visibility/presence rate is exponential. I don't have the right formula yet... ;=}
Before getting the shrimp, I double checked the water compatibility.
Then before adding the shrimp, I fed the fish with a nice helping of varied live food, to help ensure that the fish in the tank wouldn't mistake the new company for big live food.
I put them in about 15 minutes before the lamps went out. First I added a curtain of java moss, which I hung up high in the tank over an area where there are lots of tall full grown Rotala Rotundifolia, so the shrimp had an immense amount of green hiding stuff and also lots of moss which they like to nibble and crawl around in.
Just before the lights went out, I saw one shrimp perusing a branch of hardwood that protrudes from the sculptured back wall of the tank.
The next day, I was initially worried about the fate of the newcomers, but then I discovered a big one crawling over a large piece of hardwood in quite another, open area of the tank. It didn't seem to mind at all being so in the open and it was very busy feeling and nibbling in the hairs of the algae there.
It was interesting to see how the fish reacted. The Barbus pentazona p.'s hung around it for a while, curious maybe, hesitant about what to do. When the shrimp turned around, they seemed to dash for its tail but thought the better of it and returned to other recreative of consumptive matters elsewhere in the tank.
The female Gourami hung over the shrimp a while, studying it up close, extending her feelers but the shrimp didn't stop working at the algae, it merely turned its own very long feelers towards the Gourami and touched the Gourami on its body here and there which might have caused uneasiness because the Gourami also left the scene without touching the shrimp further.
In the first week, we usually saw between 1 and 7 shrimp within 15 seconds when we look carefully. The visible ones are usually walking on the hardwood, sometimes they all align with the tails upward, grazing the wood methodically.

After about three months, it seemed all 12 shrimp had disappeared somehow. Some may have died, some may have been in permanent hiding. Also, they are quite nocturnal in that they seem only to come forward during daylight hours when they live in great numbers. This might explain why shrimps that come from a densely populated tank first walk around during daylight but when they find out they are small in number, they grow more shy and hide during the day.

Wim Prins, the first breeder of C. serrata that I met, told me that when he started out with these shrimps, he got 10. He found few dead ones, and then it seemed none was left. A little later he got another 10, the same happened and he gave up. Months later he discovered a few shrimp in his tank, a day later some more and from there he grew a population of hundreds... Regrettably he lost all of them over a very warm summer later on.

In my case I saw some small shrimp three months after the first 11 were put in. I wrote in my log:

By the way, I have discovered baby shrimp! The Caridina that grew fewer and fewer in number, down from 12 to about 3 in visibility, has spawned some time ago because when I looked through the tank with a tiny flashlight yesterday evening after dark, I noticed two 5 millimeter long very exact bee shrimp (no doubt, the stripes and all) hiding in a very small crevice between bog wood and sand substrate, where no fish could reach them.

I must tell this to Wim Prins, the man who gave me the first 11 specimen. Every time I see him, he asks me how his shrimp are doing, and until now I could only report some hopeful signs (empty shells of shrimp that changed skin), one bad sign (one dead shrimp) and the doubtful sign of shrimp seemingly disappearing, all but the three that I rarely see.

During the day, one sometimes carefully and slowly climbs down a steep piece of hard woord, but in the night they jump from place to place, much like a butterfly hovers from flower to flower. Interesting behavior!

Shortly before writing this, Wim Prins had come by to donate another dozen. I wrote:

Wim came by and brought along 11 extra shrimp. He first inspected my tank critically to see if it was good enough for his shrimp and I passed this visual test ;=}

When we gave the shrimp to the tank, they merrily landed on a hardwood spot and like a herd of sheep they openly grazed the algae field there. Not at all shy! Wim explained that he had observed in his tank how the shrimp seem to feel more at ease when they are in a "school" together.

In his tank, his shrimp population had had some bad luck and was halved, from about 200 to about 100 in number, so he's keen on getting populations successfully breeding in other locations as well, so if his population suddenly perishes for some reason, there will be a fall back option.

When the shrimp arrived in the tank, father Badis, formerly believed missing in action, appeared around a corner. As this was for the first time in many weeks, and he was looking great, I quickly called J. and she called out for the kids to come down to see father Badis. Wim was very amused by our shouting "Look! father Badis is here! He is o.k.!" Wim slapped his knees in great merriment.

I've been taking care to constantly provide some dead unfrozen food for the shrimp to eat. I hope they thrive...

G. Laarhoven from Groningen visited our aquarist society and he gave an interesting lecture about Caridina serrata shrimp. He showed great slides of these, featuring the "crystal red" variety and the more common types with black stripes.

He showed some spectacular slides of shrimp that he and his wife have been breeding in the past years. Very little is known and published about shrimp. The Smithsonian Institute has several publications but for the average aquarian very little knowledge is available. Some species have proven very hard to breed. Laarhoven managed to keep fry of one species alive for a maximum of 12 days, but the best / ideal food to provide for some species of shrimp fry has yet to be found.

My "Caridina serrata" are are livebearers according to Laarhoven. In the female's belly the eggs grow but shortly before coming out and their release from the mother's belly, they can be seen (as I *have* seen a few weeks ago, not sure of what it was that I saw) crawling by the dozens behind the transparant belly skin. When they come out they are extremely tiny but formed and modelled like the big ones.

For food, Laarhoven had a great suggestion: the shrimp are very very fond of trout food that I must get from a shop catering for fishermen. I will surely try that out a.s.a.p.!

(Note added later: there's also something to say against this "trouvit" trout food: the wide spectre antibiotic that's in the food has the advantage of killing many bacteria and stimulating growth, but the disadvantage of also killing useful bacteria and producing later resistance against treatment with antibiotics.)

Mrs Laarhoven also told me that these shrimp are not very critical to the temperature and hardness of water. If they don't die, you have LOTS more than you think you have. Once, when they thought they had about a hundred, and a shop owner wanted to buy a supply, she easily caught over 200 of them and still the tank didn't look deserted by shrimp!

They said the shrimp likes to eat the roots hanging from a plant that in Dutch we call "Braziliaanse klimop" (Hydrocotyle leucocephala) which literally translates like "Brasilian ivy". This besides these shrimp being fond of java moss and Riccia fluitans, as is well known already.

One malaysian shrimp has umbrella front feet and constanly holds them out to catch the tiniest food in fast streaming water. Laarhoven never managed to find out *what* food it was waiting for and eating. Flake food particles were immediately thrown away by this shrimp. It had fry a couple times but his never succeeded. The fry was whirling helplessly in the tank and the mother kept the umbrellas closed, likely to avoid her own fry getting caught. The fry didn't survive. In the bigger biotope, the fry whirls away out of sight from the mother.

On the subject of medicine, Laarhoven said to be careful. When he once accepted a couple of Cardinals from an acquaintance, thus introducing a disease that I think is called "ich" in English ("stip" in Dutch), he treated this with "exit" produced by Velda. It treated the disease fine, but hundreds of shrimp died and a surviving species was rendered infertile, never had fry afterwards anymore. My experience has been that Cyanocell, a pill to kill blue algae, does not bother the shrimp at all.

I also set up a small special tank 50 liter tank with hardwood, Riccia fluitans, java moss and some crypto's to facilitate Caridina serrata shrimp. I bought 25 (mainly small reds) at an aquarist meeting, and another 25 (common variety) from Wim Prins but... almost all of these died. The only ones that probably didn't die, were four of the last seven that survived when I took out the hardwood and all plants except the java moss. I cleaned the tank, rinsed the fine sand substrate with hot water and started up the tank again, filling it with the good water from the 200 liter tank. Three went in the special tank again, four into the big tank. Of the last three, two died within two days, and the last one, with eggs, held out a few days longer and then also died, regrettably without any clue as to the why of it. The experience was rough, sobering and while the dying was going on I even felt the impulse to totally quit the hobby. There's only so much helpless slaughter one can take. I soaked the logs in salted water to clean them.

By the way, the breeder that sold me the reds told me they like brine shrimp (artemia) a lot and his guess is that these red brine shrimp keep his shrimp so clearly red in color. That would be interesting, because Mr. Hisaya Suzuki says he got them red by selecting...

While the shrimp in the special shrimp-tank were dying, the shrimp community in the bigger tank seems to grow! They survive amidst predators like the Badis badis, the Kuhli loaches and the Barbus pentazona... I logged:

The nice thing is that yesterday evening I observed about five shrimp in the big tank, each perusing and cruising the substrate and stones in the tank. Two of these were rather small of a size I never put in the tank, so they must be next-generation shrimp. Maybe the shrimp population in that tank has made it through the dire straits...

Since this experience, I restarted the small tank and while observing a tank with shrimp in a shoip, I noticed that this tank had much more water flow and air than my small tank had. I cleaned the water of the shrimp tank with carbone in the filter and I used an air stone to keep a flow of air bubbles, the air pump working at night (when the noise won't bother anyone). I purchased some shrimp here and there and they thrived! For a few weeks, about a dozen shrimp lived in this tank before I added more. Two of this dozen were another species, grey-brown with a white stripe from head to tail, but with about the same body size and refined shape as the Caridina. Nanne de Vos and Jochem 't Hoen have both had this species before but they never managed to breed them.

Then I added more company, writing:

Date : 1998 Fri Jun 05, 20:48
I found a private breeder, Bouman in Ede, offering Caridina serrata and I visited him this morning, bringing home a good number of these shrimp in all sizes. Some adult, others younger and also a dozen or so very miniminiature young specimen, of only a millimeter or three long! Very cute fellers.

TIP 1 from Mr Bouman: take care when putting them in the tank that any fish in the tank won't assume you're trying to feed them shrimp.

This is what I did after letting the plastic bag float for 20 minutes: I floated a plastic container with small slits in it, emptied the bag in this container so the shrimp were IN the tank but also in their own bag water which started to mix slowly with the tank water. The fish in the tank could see the shrimp but not get to them. I also fed the tank well with live food. I gave the shrimp some dried flake food which they LOVED, they're used getting it from Bouman so I saw all of them, tiny and bigger ones, throwing themselves on the flakes and devouring it. I was surprised to see how fast and how much they can eat. Bouman told me that he thinks a reason for shrimp unexpectedly dying in tanks is they often don't get enough food for their appetite. Still, Bouman has some unexplained casualties as well in his Caridina history: of the five similar tanks that he has had Caridina populations in, two tanks had very bad luck while the three others have bred fine, yielding thousands of young shrimp. He never figured out what was wrong with the other two tanks. Oxygen, I wonder? Bouman did observe that on hot days the shrimp stay higher up in the tank.

I put one bag in the big community tank, two in the special shrimp tank. In the community tank, after a while the shrimp were all done with the flakes, leaving finer particles uneaten for the time being. They started to climb the walls of the container and I judged they might be ready to peruse the tank at large. I slowly turned the container over, letting the water flow into the most densely planted part of the tank where plenty of Rotala rotundifolia offers hiding places. I saw one tiny shrimp heedlessly paddle towards the front pane. One Barb quickly approached it, asking "Hey, you, STOP! You're FOOD, aren't you?!" but the shrimp flipped it's tail and startled the Barb by being suddenly in quite another place inches away. Another Barb arrived with the same greedy, questioning look and !spt!, the shrimp flicked away into the Rotala brush ;=}

Even though I have a horrific headache today and most of the day has been lost, this shrimp episode has made it a successful day after all (plus I saw two videos I'd saved to see a long time, "E.T." and "Wall Street", both relatively entertaining with an aspirin. And I went to see our horse Kasper and bought him new shoes. There's plenty of time to mess around with shrimp, horse and ibuprofen, since J. & Lore are in Paris for the weekend and Veerle is staying at a friend's house tonight.)

TIP 2 from Mr Bouman: know how simple some clever breeders get their shrimp orange in color? Feed them CARROTS! Yes, carrots. The thinnest slices, preferably cooked (slice AFTER cooking), but they even nibble them raw!

Date : 1998 We Jun 17, 22:20
Today, to celebrate that Jochem passed his final exams with flying colors, (as did my eldest daughter Lore on hers today!) I treated the shrimp with carrots.

From a glass jar of perfectly orange, fat baby-finger-sized precooked carrots I took two short fingers and put one in the small tank, one in the other. There were peas in the jar too so I also handed out a few of those.

The peas drew some attention, but no real passion. But the carrots got shrimp frantically hacking away at them! It's nice to see how, with the orange background, the eating arms of the shrimp can be observed pretty good. Two arms look like they have primitive two-fingered hands to grab things and bring them to the mouth, two arms look like they each have a pair of the tiniest crab's scissors on them that can be used to cut and dig.

In about an hour, the carrots had holes dug into them. A shrimp at one end had been digging right into the sweet center of the carrot.

The advantage of this type of food, at least in the big tank, is that the other fish in the tank are totally indifferent to the carrots. The barbs have shown some fondness of peas in the past but they haven't taken a second look at the carrot, so the shrimp can nibble the carrot without any fussy fish disturbing their dinner.

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This page is linked to the home page of Frans Goddijn.
Frans Goddijn, Postbus 30196, 6803 AD Arnhem, fax +31 (0)26 3211759
Updated Mar 8, 2002