- How many fish can you have in a saltwater tank?
Lots, but do you mean how many fish total in one tank?
Or do you mean how many different types
of saltwater fish can live in the same tank together?
Or, perhaps, how many different saltwater fish
species are there to choose from
that are able to be kept in a home aquarium successfully?
Or most importantly, how do I pick a great community
of attractive and fun saltwater fish for my tank?
Let's get those answers.
First, there are hundreds of saltwater fish species
that do well in our home aquariums
from small nano fish, like gobies,
blennys, damsels, cardinals and small wrasses,
to tangs, angels, dottybacks,
basselets, anthias and the list goes on.
And there any more types of fish than that,
and many species within each type
making for an incredibly long list of fantastic options.
So you will most certainly find
a whole bunch of fish that tickle your fancy.
Many of those fish are able to live
in a community of different species,
while some others might be somewhat
or even very aggressive towards their tank mates.
But again, there so many different fish to choose from.
You can have a tank with a very diverse
community of saltwater fish,
even when you avoid those less-friendly tank mates.
And I'll pull you in the right direction
for selecting a good community of different fish
for your tank in just a little bit.
Now, when it comes to how many saltwater fish
you can keep in your tank, that depends on a few factors.
First and most importantly, the size of your aquarium
is going to play the biggest role
in the number of saltwater fish
you can comfortably keep in it.
And not just the total number of fish
you can have at once but also the number
of different species it's appropriate for.
For example, while you can fit quite a few nano fish
in a 40 gallon cube tank,
you wouldn't be able to keep even one adult blue tang
because the tank just doesn't give that larger
and very active swimmer enough space.
It's also best to look at not just
the volume of the aquarium, but also the dimensions.
A 40 gallon cube or a 40 gallon tall aquarium
offer less usable space than a 40 gallon breeder
that is shorter, but longer side-to-side
and wider front-to-back.
In other words, larger tanks that are longer and wider
have a larger pool of fish to choose from.
And at the same time, the larger the tank is,
the more fish you can comfortably fit.
How many fish you can fit in that 40 gallon breeder
example tank can range quite a bit
depending on the adult size of the fish,
as well as the type of habitat that they prefer.
Some fish are very small
and they really don't add much waste to the system.
While larger fish tend to eat more and make more waste.
Some fish prefer to hang out in open water
in the middle of the tank,
while others prefer to live closely amongst the rocks.
Some prefer to perch on the corals
and others stay on the sand bed.
If you find fish to fill
each of these separate habitats in your tank,
you'll be able to keep more fish,
since they won't be competing for space.
And because your tank is only so big,
if you prefer to keep larger species,
you'll keep fewer fish in total
than if you kept some larger species
and some smaller species.
And even more, if you kept only smaller species.
Some fish can also be quite aggressive
towards their neighbors
and sometimes only to very specific neighbors.
Clownfish are a great example.
They're a good community fish if kept alone or in pairs,
but often become very aggressive with other clownfish.
So one species of clownfish per tank
is usually the best bet, but at the same time,
clownfish are rarely aggressive towards other species
and do very well in a community tank.
That pair of clownfish will also share
the same small territory in the tank,
so whether you have one clownfish, or a pair,
the number of other fish you can keep in that tank
stays roughly the same.
On the other hand, some fish like the Six Line Wrasse
will add very little waste to the tank,
but need a huge amount of territory to themselves
if you want to keep other fish
that like the same type of habitat as them.
Otherwise, they become huge bullies
and can even kill their tank mates.
Now, even though selecting a good community of fish
for your tank is a little more nuanced
and doesn't have a one size fits all answer.
We all want to start off with some really cool
and awesome-looking easy to keep community fish.
And you can click here to check out
the top 10 best options for beginners.