Question/s about Mandarin fish and copepods

[LovemyFish]

I have a 50g tall tank with somewhere around 45 lbs of live rock. It has been set up for almost a year all tank parameters are normal, temp about 76f.
Now, I just purchased a very nice Mandarin, only to find out he wont eat except what he finds on the live rock, this may be ok for now, but I fear it wont be enough for this really cool fish.

I know that copepods are a big part of their diet, so here is my question/s.
How can I tell if they are in my tank?
How do I know if I have enough?
Should I go buy some and put them in at regular intervals so that there is enough natural food for him to survive?
Can you have too many copepods?
Is there an alternative food source that will also work?

I really love this fish. It was the inspiration for me getting my salt tank, I waited a whole year and have taken very good care of my tank. After some recent reading I have decided to add a 14g refugium to this tank, even though the conditions have been exceptional since it's first cycle. I feel lucky to have this fish and I hope I can keep it alive as long as possible.

Thank you for any input.

[Ninong]

Now, I just purchased a very nice Mandarin, only to find out he wont eat except what he finds on the live rock...

Unfortunately this is a common problem with these beautiful fish.

...this may be ok for now, but I fear it wont be enough for this really cool fish.

This is why the usual recommended minimum tank size is at least 75 gallons. Actually it's the amount of live rock that counts more than the volume of water, especially live rock rubble and live rock near the sand bed. It's also very important to have a nice, lively sand bed if you want this species to thrive.

I know that copepods are a big part of their diet...

Harpaticoid copepods are their primary natural food item, representing possibly as much as 90 percent of their diet. They also eat fish eggs, gammaridean amphipods, ostracods and polychaete worms.

How can I tell if they are in my tank?

Wait until all lights in the tank and in the room have been off for about two hours at night and then check out your tank with a flashlight. If you use a red flashlight, you should be able to observe without being detected. If you use a regular white flashlight, you will have to look fast because every place the light hits, the copepods will quickly scamper away into their hiding places. They are very tiny, much smaller than amphipods but their movement is unmistakeable. They should be all over the place. All over the exposed live rock surfaces and the sand bed.

How do I know if I have enough?

You start out with a lot of really good live rock. You wait at least six to ten months. You do not add any over similar fish that feed on the same food items. You continuarlly check your tank at night maybe once every couple of weeks to see how things are coming alone. You can purchase some amphipods and copepods from a few different sources online but shipping is a killer unless you are ordering other stuff and adding these to the order. I have ordered from both Inland Aquatics.com and IPSF.com.

The most important thing is the quality of the live rock you started out with. It should already have a lot of copepods. Then you wait at least five weeks before adding your first fish to your tank and you make sure that it is a grazer and not a fish that eats tiny copepods and other benthic critters.

Should I go buy some and put them in at regular intervals so that there is enough natural food for him to survive?

Well, the trick is to have a population that is self-sustaining. This is not all that hard. It's easy to do. It's also easy to mess up because there are so many ways to go wrong. Again, that's why everyone recommends larger aquariums, like at least 75 gallons, although some people will tell you 100 gallons. Then there will always be some guy who will post about his mandarinfish in his 25-gallon tank.

Can you have too many copepods?

No, absolutely not. You can't have any more than can be supported by available resources. Besides, they are valuable food for so many different species of fish. Copepods eat phytoplankton, as well as detritus, so you might consider adding some D.T.'s live phytoplankton a couple of times a week just to feed the copepods. Add it about half an hour to an hour after all lights go out. A teaspoonful would be enough at one time for your size tank.

Is there an alternative food source that will also work?

Sure, there are lots of alternative foods but none of them work as well as their natural diet. In fact, they might be eating a lot and still not thriving because they're eating the wrong stuff. Some people have trained them to eat flake food, frozen mysid shrimp, tiny pellets for carnivores, just about anything clownfish eat (but not any algae), etc.

I hope I can keep it alive as long as possible.

Create a rubble zone in your tank if you don't already have one. Get some small pieces of live rock and spread it out across an area of sand bed in a nice private area or an area that you think your mandarinfish would find cozy. Very small pieces of live rock work best. Pieces in the 1"-1.5" diameter range. In other words, create a shallow rock pile as a place for the copepods to hide and thrive and a place for the mandarinfish to hunt for them.

It's possible to keep a mandarinfish in a smallish tank such as yours but it requires more effort on your part. If you had a 180-gallon tank with 250 lbs of live rock and you waited a year before adding your mandarinfish, you wouldn't have to worry about it not having enough to eat.

Good luck!

P.S. -- What other fish do you have in your tank with your mandarinfish?

[LovemyFish]

Thank you for the info!

The only other fish in the tank are a couple of yellow tail damsels, a chromis and an ocelaris clown, other than that, some hermits, turbo snails, and a coral banded shrimp.

I looked last night and saw a bunch of small opaque shrimp looking creatures moving about in the sand bed and the rubble that you mentioned, there are also a whole lot of tiny little white critters i saw but they are too small for me to describe.

Ok, so I feel bad for jumping the gun on getting this fish. I will endeavor to do my best to keep this fish healthy. I am buying more live rock from a friend who has a very well established tank. Is it possible to put too much rock in my tank what's the max for a 50g I can take the damsels back to the fish store if I have to to keep this fish happy.

[Ninong]

Adding some live rock from a healthy, established aquarium will definitely help. How much live rock you can stick in your tank is really up to you. The general rule of thumb is that you should have one to two pounds of live rock per gallon of volume of the aquarium, but that's just a general guideline, nothing more.

Most people add live rock until they reach a point where they are satisfied with the appearance of the tank. That could mean that the live rock takes up one-third of the available tank volume or it could mean that it takes up half the available tank volume. It's entirely up to you. I would say that for a 50-gallon aquarium, you should probably have somewhere between 40-80 pounds of live rock. You already have 45 pounds of it, so maybe adding another 15-20 pounds would be a good idea. It's up to you. Don't forget to leave space for the fish to swim around. And always construct your rock structure so that it has lots of hiding places and caves that your fish can each call their own.

As far as the damsels are concerned, that's another thing that is entirely up to you. If you really like damsels, then keep them. Just remember that most damsels are quite aggressive. If they are bothering any of your other fish -- like maybe your clownfish -- then you may want to consider removing them.

Most of the critters that you see moving around at night are good guys. The bad guys are the ones that attach themselves to the fish. If you see any parasites on your fish, that's when you have to start worrying. Chances are all of the critters you saw are good guys.

Good luck!

[LovemyFish]

The damsels were the starter fish for this tank, the clown was added about 3 months ago and he seems to control the tank. All of the fish leave each other alone so no worries there.
I was just thinking, with less water due to the volume of displacement caused by adding another 30+ lbs of live rock, should I worry about adding a refugium? (I don't plan on adding any more fish to this tank, I really just wanna create an atmosphere this new Mandarin will thrive in. Even if he is the only fish in the "sea"). I have 14g and 10g tank sitting in my closet.

[Ninong]

If you decide to add a refugium, that's always a good idea.

[leebca]

I'm sorry LovemyFish, but Mandarin husbandry is an uphill battle. There are not enough variety of pods in a closed system to have them thrive. They will survive for some time, but not thrive: Survive or Thrive?

There are two primary reasons:
a. The pods in a closed system wax and wane depending upon predators, nutrients available, and the environment -- the home aquarium isn't stable enough to maintain a wide range of pods. For instance, the carnivore pods often wipe out much of the others, then die back (eating each other), then other populations come and go.

b. The nutrients available to the pods in a closed system is limited. The pods only feed on what is put into the tank and if that isn't pod food, then the pods themselves reduce over time in nutritional value.

The right thing to do, is to train the Mandarin and all pod eaters to eat prepared foods. Thus their nutrition is assured; they will thrive not just survive. You'll learn more in these posts:
Food Presentation
and
http://www.reefland.com/forum/marine...tml#post186916

Please read the above. ;)

[reefer@zoom]

word to the wise....get rid of the damsels.