New to saltwater fish

[dallas721]

Hi! So I'm new to saltwater fish. My husband got a 16 gallon biocube for our sons 5th birthday. So it's about 7 months old. We got a firefish today and right away our supposed peaceful flame cardinal started attacking it. Unfortunately I don't think that the firefish is going to make it. I do not have a second tank to separate the fish. We lost a blood red shrimp while on our cruise. It had been in the tank about 3 weeks and everything seemed fine. Now I'm thinking the flame cardinal had something to do with it. Any suggestions? We also have 2 clown fish, a nightwatch goby, tiger pistol shrimp (who rarely is seen). Any help would be great

 

[JumboShrimp]

A 16-gallon BioCube is very small. (I have one.) Whether you have 2 fish, or perhaps (?) three, choosing the right fish will be crucial in terms of compatibility.

 

[tnreef]

Maybe too crowded with not enough rock work to hide. Depending on size of the other fish as well and food availability. 16 gallons is pretty small. Take into account the fish grow too clowns can get up to 4+” watchmen as well.

I can tell you guys are loving and getting into the diversity of the hobby maybe upgrade to a 32 biocube or even a 40 breeder.

 

[dallas721]

So we've been checking in with the guys at our local store and world wide coral when we visit, prior to adding something into our tank. We've been told 5 fish max. Our nightwatch goby pops out every once in a while. The clown stick to the top half and back of the tank, while the flame cardinal sticks to the middle and in the caves our rock has. Flame cardinal was the last fish introduced. The blood red shrimp liked the caves as well, and things were great for about 3 weeks. We came back from a cruise and found our shrimp dead in 3 pieces. Our pincushion sea urchin was taking care of the pieces. My husband took out what he could so it wouldn't affect our tank too bad. So my son picked out the firefish and right away was nipped at by the Flame cardinal and it wasn't even near his cave. So I'm wondering if it was the reason for our blood red shrimp to die.