copepod identification?

[Kyliegirl]

I have recently purchased and begun setting up a 25 gal reef tank. now one of my focuses was to own a mandarin, so I was asking the reef shop about copepods and he took me to a tank where round white things crawled along the surface of the glass. I am not sure if these were copepods as there seemed to be only one egg sack to the naked eye, and they looked like circular creatures.

Would these actually be copepods?

I mentioned to the reef guy i was going to culture pods for the mandarin, in his defence he said I would probably pick up things i didnt want to culture, which may be so but I think if i grab the copepods on the glass, i shouldnt really grab anything else but the pods on the glass...

 

[Anonymous]

Maybe amphopods? Copepods are small, I'm not sure that you can see an efgg sack on a copepod without a microscope. But, dragonettes will munch amphopods, too.

You can get a pure culture of copepods. I raise a lot of them using a brown diatom (phytoplankton) and a pinch of spirulina powder.

 

[Anonymous]

I am not trying to be confrontational, but if you do not even know what pods are yet, I would avoid trying to keep a mandarin for a while until you learn more about marine aquariums.

They are not an easy fish, they have usually high mortality rates, and I dont believe a 25 would be large enough.

 

[minibowmatt]

i have read that the common consensus of system size necessary to feed a mandarin should be at least 60-75G. Now I could see a 25G tank being fine for the fish itself, but it will clean out a 25G tank of every pod over one or two nights, not leaving any to breed and build a larger population. If you have a BIG sump/fuge to grow pods in to feed the smaller tank, I think that would be acceptable.

 

[fyrefysh]

I would say, get an HOB refugium with some live sand and rock rubble, wait six months and GO FOR IT! Make sure that no other fish in your tank are going to compete with the Mandarin for food (such as pseudochromis, etc.) You never know what you can do unless you try. :wink: Don't let these guys scare you away from what you want to do.

 

[Meloco14]

While fyrefysh gives good advice and I am sure is well intentioned, I will have to disagree in that I don't believe we should "go for it" and "just try" anything when we are dealing with living animals. I do agree no one should be scared out of doing anything in this hobby, but rather make sure you are well informed before doing it. Now I am hoping Kyliegirl is well informed, and she is at least on the right track in securing a food source. To answer the OP, what you saw probably were in fact copepods. You can find good sources of copepods and amphipods online. IPSF and inland aquatics both carry live pods and there are others as well. I believe there is a thread in the nano forums about different places to find live copepods, you might want to check it out. Other than that, I agree with the above posts that you will want your tank to be well established and have a refugium or a separate grow out tank for the food source if you intend to keep the mandarin in that tank. Good luck.

 

[Kyliegirl]

thanks, I am planning to have culture tanks for copepods so i have a continuos source for the mandarin,

I am aware how fast they eat all the copepods in a tank. But the manadarins they sell here are all trained to eat brine shrimp etc. I am sure with some work I could get the mandarin to eat gold pearls etc so it gets the nutrition it needs. I preffer to try and culture pods for the mandarine tho, as its their natural food source.

I was just doubtful about these critters being copepods (even though they may differ in size/shape here in aus) , as I thought copepods were thin and long, not roundish. but they do look fairly small for the mandarin to eat. and the reef guy showed me the amphipods in the gravel , which were rather huge.

 

[Anonymous]

The could be Sandskaters. If you can get a good look at the top of them and can tell how many eyes they have. Copepods only have one eye.

 

[Meloco14]

If you go to the hitchhiker faq here and go to the rocks/glass page at the bottom there is a good picture of the common amphipod. For copepods try searching online, there should be a lot of resources with good pictures for you. It sounds like you have a good grasp on the feeding but in case you weren't aware brine shrimp have close to 0 nutritional value. So when you use brine shrimp to feed make sure they have been enriched with vitamins, or soak them in vitamins yourself. Mysis shrimp are much better food if you can get the mandarin to eat them. HTH

 

[Anonymous]

Here's a Tigriopus californicus copepod

picture from www.Reef-Nutrition.com
Photo by Dr Eric Henry

 

[Kyliegirl]

thx GreshamH, but as i said before, i dont know how different our pods might look here in australia.

Which is why i asked in the first place, I seen a few images of different types of pods, but as the sites state, there is over 12,000 species of pods.

thus why i asked if these glass crawling critters may be pods.

I think when i go in for my live rock i will request them to collect some of these critters on the glass and add them to a tank with a mandarin and see if it eats them, if it does, they are definately pods. If it doesnt, then I will know they arent pods, or a reliable food source for the mandarin, just so i dont culture them and then realise the mandarine isnt happy with its order and demand a refund

They definately dont look parasitic as theyre in a tank full of fish and live rock.

they were too small to see their eyes, my face was very close to the glass to see these little crittes, there was thousands on the glass, but i didnt see them until i was close to the glass. they were just small round white specks, like grains of sugar, the ones with eggsacks looked like two round sugar grains stuck together, only the egg sack was slightly smaller. they only carried one egg sack. not two from what i could see.

edit- just looked at the site, when i look at it, those rotifers look like the small white things on the glass i seen. just i dont think they are because rotifers are microscopic arent they?

 

[fyrefysh]

I would assume that what you are seeing is a type of isopod, I have them on my glass as well. These are also a good food source of a mandarin.

 

[Anonymous]

Well you don't have rotifer running around, I can pretty much say that with certainty They need to eat every 4 hours, or they die. They double in population in 24 hours, so your tank would be swarming if it were them.

That copepod I posted is a very good representation of a herpactoid copepod, regardless of which country your in.

FWIW, many copepods look like rotifers to the naked eye. That one I posted is one of the larger of herpac's around, coming in at 2,500 microns at full size. I suspect what your seeing is in the 200 - 400 micron range. In the copepidite stage, the tigriopus look like rotifers to the naked eye as well.

If you could post a pic, I could have it ID'd for you. I work with several scientists that just happen to be copepod nuts.

 

[Meloco14]

From your description it sounds like they are some type of copepod, or something similar. Regardless, I am pretty sure they will be good food for the mandarin. I am sure they aren't rotifers, AFAIK rotifers are only found in freshwater. If you have your tank already established at home, you should look carefully in there to see if you have any copepods. Pretty much any tank with live rock will have them, unless something is eating them all already. If you do have some, you may be able to catch them and transfer them to a grow out tank. Another idea would be to create a pod pile, or a little pile of rubble in your tank. Let it sit for a couple weeks, then pull it out and place it into the food tank. That should contain some copepods. Larger food like amphipods tend to congregate in macroalgae, and I also find a lot among my filter pad in my little HOB filter. If you have either of these you can easily transfer some pods into a separate tank. HTH

 

[Kyliegirl]

ok i put live rock in my tank, i am glad to say i managed to get a baby snail hitchhiker, by the shape of its shell possibly a trochus. its very small..

now, the copepods..

I am very pleased to say I spotted the common copepods in my tank, the long thin ones.. i had to squint very hard to find them, but they are there, along with a few of hose round ones i was talking about.. unfotunately i dont have a magnifying glass, and my camera is very cheap and it couldnt focus the little guy.. so i cant supply a picture..

I am worried now how i can nab these smaller copepods and place them into a small cultivating tank.. they are extremely small..

 

[Anonymous]

. I am sure they aren't rotifers, AFAIK rotifers are only found in freshwater. HTH

There's a true marine rotifer, freshwater rotifer and a brackish rotifer. I grow billions of rotifers that live at 1.015 - 1.021 sg every month

Most the aquaculture industry is on a brackish rotifer strain, typically referred to as "L" type.

http://www.rotifer.com

 

[Kyliegirl]

i just had an idea. i picked up a rather snazzy live rock which when i look at it, actually looks like a skeleton of a coral. it just so happens to be in a cage like shape, would i beable to place an algae scrubber pad inside this so the copepods have a place to breed and cultivate inside the tank?

they seem small enough to crawl and play inside the scrubber, its white packed wool or something..

 

[pwj1286]

Young tanks seem to have an explosion of microcrustation popluations and then seem to decrease over a few weeks to a month. As a few months pass, a smaller explosion will occur and then decrese and level out, to the ecosystem's ability to support that population number.

Populations can also increase or decrease depending on the ecosystem's homeostasis status.


This has happened in my own expirences.
_________________
Honda CL100

 

[Anonymous]

Excellent idea kyliegirl. I use something similiar on a commercial scale.


In the wild, you have a phyto bloom, followed by a copepod bloom. This same cycle is recreated, as pwj1286 said above, by the typical diatom bloom most tanks see during the initial cycling of the tank.

 

[Meloco14]

There's a true marine rotifer, freshwater rotifer and a brackish rotifer. I grow billions of rotifers that live at 1.015 - 1.021 sg every month

Most the aquaculture industry is on a brackish rotifer strain, typically referred to as "L" type.

http://www.rotifer.com

Interesting, I learned something new today. Thanks for the info!