get a fuge.
either a HOB or a separate tank. Or you can do a standalone fuge and just shake out the cheato into the tank every now and then. You can use the 'soapdish' idea:
you have to have some SAFE place for pods to reproduce without getting eaten. You should also try to find a fish that already eats frozen, or at least live brine so you can start to try and train him to eat prepared food. Many mandarins will clear out your pod population in a matter of weeks, and then they starve.
Check this info out:
""Feeding Methods and Tips
Mandarins fish are methodical predatory grazers that will search every corner and crevice for a tasty morsel. These fish sometimes appear to be tireless in their almost constant pursuit of the small live prey that lives amongst the rock and sand of a healthy and mature reef aquarium. Whenever they find food they will hesitate to look at it, and then strike at it with a bird-like pecking motion.
Because mandarins are slow eaters (and sometimes don't appear to be terribly bright either) it is a good idea to give them as many advantages as possible whenever offering supplemental feedings. One of the first things that should be done before offering any supplemental foods is to temporarily turn off all the pumps. Otherwise, about the time your mandarin makes up its mind to eat a sample of your offering the water pumps will move the food away in the current leaving the mandarin looking a little confused as to what has happened.
If your mandarin shares an aquarium with faster or more aggressive eaters you should try to reduce the competition. One of the ways of doing this is to offer foods that mandarins don't normally eat to the other fish first. Personally, I like to feed small quantities of several types of food at each feeding, so I just offer things like dried seaweed and freeze-dried or flake food first. Once the faster eaters have had something to eat they may not be quite is aggressive. Distributing the foods throughout the tank rather than feeding in one spot will help the slower feeders to get a better share. Once the other fish are occupied eating your prior offerings you can then target feed your mandarin. Concentrated portions of food can be deposited near the mandarin will use of a turkey baster. Sometimes fish will appear to be frightened when approach with a turkey baster. Move the turkey baster slowly toward the mandarin and stop if the fish begins to move away. Fish can become conditioned to associate a turkey baster with feeding if it is used repeatedly, and with a little practice you will get the knack of using one.
Live brine shrimp feeders can be handy little devices for keeping supplemental foods available for mandarins, seahorses, butterflyfish and other slow eaters. Adult live brine shrimp are accessible through the feeding cage. The brine shrimp will stay inside the feeding cage so they will not get caught up in mechanical filtration and the pumps do not have to be turned off during feeding. You can find out more about these ingenious little tools by contacting Urchin Searchin Enterprise, email:Urchsearch@aol.com.
Quarantine
I am a firm believer in preventive measures such as quarantine, but this can be problematic with mandarins. These fish need a constant supply of live foods available for long-term survival. Copepods, primarily of the Harpacticiod species, are the mainstay of this fishes diet, at least in captivity. A large supply of these and other live foods are not usually found in quarantine tanks. If your mandarin happens to be a specimen that quickly acclimates to new foods you may be able to sustain it for couple weeks with supplemental feedings of live brine shrimp, blood worms and other live foods. Even specimens that are slow to accept new foods will usually eat newly hatched baby brine shrimp. Some specimens will learn to accept frozen mysid shrimp, worms, or brine shrimp. Some people report having good luck using Sweetwater™ zooplankton.
Another approach to quarantine with a mandarin fish is to place them in a tank that is used as a food farm. They will quickly begin to decimate the population of these foods, unless your food farm was prepared months ahead of the mandarins arrival. I have a small aquarium that contains live rock and sand that I use to raise copepods, amphipods and other lives foods. I can place a mandarin into this tank for a couple of weeks of isolation. Yes, these little Jewels do require some extra effort and special attention, but they are worth it! Once a mandarin has become established in well-seasoned reef aquarium, they don't demand nearly as much extra effort.""