Newbie needs help questions


New Member
Hi I have a few questions regarding arowana that I'm asking for my father. Atm we have a 72/24/18 135 gallon tank housing a 10in cross-back gold, and a 6in chilli red in a smaller tank. What I'd like to know is:

1. Is the 135 tank large enough for the 10in fish?
2. Is it safe to put the chilli red in it together with it?
3. How big of a tank would we need if we were to put together 5 aro's? One 10, two 6, and two five inch. How many gallons/dimensions

Thanks for replying.


New Member
well to start a 10 inch is fine for 135g for now but I would upgrade it to at least 180g.

2. It is not safe to have your chili red together at this young and the size different is too much so they can't not take the beat up and one will die, but you can also try and it might work out but you need to keep an eye on it in case it goes bad and remove them immediately.

3. For the size of your aro now 5 will do fine in 180G but I am a little concern about the size different and again young stage as the 10 inch can easily kill the small one. If you do add them please get them all the same size unless they are 14 inch and up then you can add them with different size and up. You also need 300G and up if you want to keep all 5 adult in the same tank.


New Member
First of welcome to the site!

I agree with hondas3000 135 is fine until the Aro is around 12''; i'd shoot for around twice the length of the fish for width but it's really up to your preference. Do you want to watch the fish swim freely or see sharp turns in a smaller tank.

As for mixing aros, its really up to the temperament of each fish and the dynamics between them and the tank. Things such as current, and dither fish will all play a role for comm-ing successes. Just be sure to observe for atleast 2 days, even if things go well for the first hours; only takes one bite to set shizzle off haha.

Based on your specific scenario I'd go for minimum 180 as hondas3000 recommended. I also agree regarding agression but you never know. Even at double the size, they could end up as being dinner?

Anyways wish you best of luck and hope you post some time; or else we don't believe you! haha jk.


Hello Welcome to the site i agree with both the above add lots of waterflow up top monitor situation for a while and have a divider ready to go. anyway you will know if its a definite NO in the first hour
as for the bigger comm tank i have a 500g lots of flow 10 aros and still they where always banged up forget about fish in perfect condition.
depend whats more important to you ... many arowana swim[ng together or arowana with no split tail , loss scales , broken barbell , riped top fin ......
but then again all these injuries may happen with a solo fish.
Two different experiences but one more stressful then the other.
hope this helps


New Member

Ur 10" aro is just fine in the 135 gallon tank.

Maybe u can consider topping water up to a few inches off the top. Pls remember to cover the top of the tank with glass cover or something heavy as aro is known to jump. :)

Aro needs length and not height.

Btw, what is the tank size of ur smaller red ?


New Member
Just to add on. To keep aro, ensure ur tank width is at least 24".

And aro like smooth and soft current, not fast and strong current. :)