I have 4 South American Arowana. Two which are silver and two blacks. They are housed in a 96x36x30" 450g tank, which I have had running since August '09.
I took some time this morning a re-estimated the size of my Arowana. I have never actually measured my aros against a tape measure, this morning I used 24" level as reference. Most recently I figured he two silvers to be close to 30", they are actually closer to 28" and my blacks are a little larger then I have previously posted.
My largest silver will be 6 years old this spring. I adopted it in poor shape when it was 2 years old and 21" long. It then spent a 26 months in a 180g tank, before moving to the 450g. It now is in the 28-29" range.
The other silver that I have had now for five years, it was only 2.5" when I first got it. Now it looks to be just slightly smaller the it's larger tank mate at 28". It was raised in a few smaller tanks until 16-18" when it was then moved to the 180g with the other silver. Where it spent 26 months before moving to the 450g.
The oldest of my two black aros I bought in February of '07 at 11". After a few failed attempts to house it with smaller of the two silver aros it then spent time the next 2.5 years split between a 5' 120g and an 8' 150g tanks. During this time it grew very slowly, I attribute that to the fact that it barely ate, most of the time eating in a week what one of my silver ate in a day. After only growing 8-9" in that time it was moved to the 450g at 19-20". Within a month of being with the two silvers it became a very aggressive feeder and was eating pellets daily along with market shrimp every other day. It grew about 5' within the first 6 months of being in the 450g and now is close to 27" long.
My baby black I got at 2" in June '09. It was raised in 55g, 75g, and 120g grow-out tanks over the first year. At one year old and 16" it was moved to the 450g, where it has continued it's rapid growth. Now at about 20 months old it is just a couple inches shorter the the older black aro, it is currently just shy of 25" long.
My arowana last spring after moving the baby black into the tank
