Planning my first reef tank - trying to decide between peaceful and aggressive.

[ECU_Pirate]

Hi everyone! First post here. :wavehand:

I want to start a reef tank and have done a lot of research on what I can stock it with that is reef-compatible. What I'm having a hard time with now is trying to decide between peaceful vs. aggressive or semi-aggressive fish.

Questions:

1. Assuming I don't intermingle the two and have followed the compatibility chart, is a tank of aggressive fish more difficult to maintain? Will they all generally leave each other alone?

2. What exactly does "semi-aggressive" mean? Does it generally mean that type of fish will pick on only those of its kind, e.g. tangs will pick on tangs? If this is the case, can you mix semi-aggressive fish with peaceful fish as long as you don't include more than one of each species of semi-aggressive in the tank? For example, a semi-aggressive tang and a black & white ocellaris clownfish would be fine in a tank with peaceful fish as long as there are no other tangs or clowns?

Thanks in advance for any suggestions you can provide!

 

[JTL]

Welcome!! You will find a wealth of information and many opinions. I know people who have broken all of the rules and still had a nice group of fish. Obviously when you try to mix known aggressive fish there is a good chance of problems. There was a point in my early saltwater fish days that I had a super aggressive mix of fish. Triggers and Lion fish living with a blue tang and never had a problem. It was a big tank and no one or at least no one that I was aware of even had a reef tank, so fish only. Since I got into reef tanks I have chosen to concentrate on corals and smaller peaceful fish. I like the fish for movement and because if I didn't have fish my non reefer friends would ask where the fish. I have typically had 100g tanks and usually have less than 10 smaller fish. Clowns, firefish, a couple of wrasses, blennies, those sort of things. Any way good luck.

 

[Valentini89]

Welcome!! You will find a wealth of information and many opinions. I know people who have broken all of the rules and still had a nice group of fish. Obviously when you try to mix known aggressive fish there is a good chance of problems. There was a point in my early saltwater fish days that I had a super aggressive mix of fish. Triggers and Lion fish living with a blue tang and never had a problem. It was a big tank and no one or at least no one that I was aware of even had a reef tank, so fish only. Since I got into reef tanks I have chosen to concentrate on corals and smaller peaceful fish. I like the fish for movement and because if I didn't have fish my non reefer friends would ask where the fish. I have typically had 100g tanks and usually have less than 10 smaller fish. Clowns, firefish, a couple of wrasses, blennies, those sort of things. Any way good luck.

The only thing I have to add is that bigger and more aggressive fish are more often messy eaters. This is definitely something to take into account when planning your system; bigger protein skimmer, etc.

 

[Sk8r]

To have a peaceful tank, a large tank helps a lot. Even the most placid fish may kill a roommate if it feels crowded. I'm building a tranquil 105 gallon, and my fish list is below. I am having quite a bit of trouble with chromis: stand off that one. But the small size and relatively easy nature of the fish below can give you a tank in which fish are highly colorful and not prone to kill each other if the tank gives them enough room.