too much fish?

ok, so ive put this up before on this site but still am not sure.
ive had 2 dominos, 1 blue devil, and 2 clowns for about 3 months now. I am about to give the little domino and blue devil to my little bro who started a 20g tank. So i was thinking i could possibly have 2 more fish but definitely 1. I DEFINITELY want a green mandarin (maybe red). but, also i would like a firefish goby. The firefish at my LFS are really small, like 1/2 inch small. So I was wondering if it would be a good idea to get both or just the mandarin. I have about 15 of live rock, and ive hand picked them from the LFS for hiding spots, so i have a lot of hiding spots. Advice would be much appreciated.

 

What size is the tank?

 

err...I would not recommend a madarin goby for a 20g tank. They eat 'pods - pretty much only pods. I would suggest a larger, more mature system in order to sustain a mandarin goby, which is actually not a goby at all, but part of the dragonet family.

 

OP would like this to be for a 20g tank.

 

the mandarin will not survive more than a week in your tank it takes atleast 75 pounds of live rock to keep a stable copepod population to feed these fish
firefish WILL jump because of damsel aggression id really re look into the fish you have in your tank even as of now let alone adding new fish

 

So it is for the 20g. Ya, it wouldn't live long as it needs a hug pod poulation to live. Even adding pods everyday would = $$$$$$$ and the mandarin may not make it then.

 

No no no sorry, I am upgrading to a 55 gallon and my brother is only gonna have like 2 fish.
but when i get the tank going ill put all the rock in and some time this upcoming week im gonna get at LEAST 20 more pounds of LR.

 

yea i know, im getting really sick of the dominos, im thinkin now that i might just let my brother have my old 30 with all the fish and rock and just start fresh on the 55

 

You could get a firefish pair if you are doing the 55, but like others said the mandarin is a no go. I would like to see a picture of a firefish that is only a 1/2" i have never seen one that small I think it would look neat.

 

I wouldn't put a mandarin in my 55, and I have 85 pounds of rock in there and HUGE pod population LOL.
Doesn't make my boyfriend happy, because he loves the scooters and mandarins, but he also doesn't want them to slowly starve to death.