I want to encourage anyone that plans to keep a mandarin goby to forget all the naysayers. People LOVE to discourage others. It just seems to be a natural human habit.
Instead of asking why it won't work, ask how will it work?
If you are willing to establish a couple of smaller tanks you can culture all the food your mandarin needs. I have 3 copepod tanks. I have a 5 gallon and two 10 gallons. I have bought macro algae plants from all over the place. Because these came from various places they came in with various types of micro fauna. Then I ordered pods
from several places online. I bought from all over so that I would get a variety of types of pods
. I also bought live rock from various places so that it too would come in with diversity. I ordered in a good algae paste and again this is something that can be bought from various places til you find a source you like and trust. I am using airstones in my copepod tanks and a variety of lighting. I have each tank set up slightly different so that should any one tank do better than the rest I can work on duplicating that in the other tanks.
I especially believe that the mixed species copepods from livecopepods dot com is a good choice because they have a 100 dollar special where the shipping is free. I've done that twice as well as smaller purchases a few times. I bought live mysis from another source as well and quite a few types of pods
came in with those. The live mysis is cannibalistic, but the hitchiking pods
stayed. I have seen as many as 6 small pod type creatures in my tanks.
I don't do water changes exactly. I have several tanks. Every day I take a small amount of water out of one of my display tanks and place it in the copepod tank and then take water from the copepod tank and put it back in the display tank. I do this several times until I feel I have managed to feed my display tank and have replaced some of the water in the copepod tank. I do small daily changes in all my tanks. So the display tank water is always in great shape.
I am careful to feed a variety of foods to my copepod tanks too. I feed flake, frozen meats, sinking pellets and the algae paste. My first tank is about 4 months old now and I can put a syringe in the bottom or on the sides or up against a rock and pull out hundreds of pods
. My other tanks are only about 1 and 2 months old and will take a few more months to get to this point.
I use the syringe method to add about 3/4th cup of water filled with pods
to my tank that the mandarin lives in everyday. I cycled that tank for 3 months using constant water changing so that the ammonia never got too high. I added pods
during this time as well. I fed that tank every few days during that 3 months so that the pods
would multiply before adding any fish at all.
If we were to buy any pet, dog, cat, rabbit, bird etc.. We would expect to buy food for them constantly. So why would it be any different for this great fish?! I think they are exquisite! I've already spent at least 400 dollars and 6 months preparing for this fish and I'll spend a couple hundred dollars more per year to continue to add to my pod population and keep increasing it.