# Planned: 260 gallon npt tank with arowana



## Wildtype Devil (Sep 23, 2011)

Hi all,

I'm planning to start a 260 Gallon Walstad style tank, housing 1-2 Silver arowana in it...

The Tank size is 84"X24"30" with 2-3" garden soil and 1" gravel cap. I plan to mature the tank for at least 4-6 months before adding the arowana (starting from 4" or so, hitting out max). Meanwhile i will add few tetra/ minnow to cycle it properly.

Will the tank be able to take Bio-load of 2 Mature Arowana and couple other small fish (tetra / Angelfish etc.)? I plan for minimal filtration with just one or two internal sponge filters along with plenty of plants (mostly Vals, swords, cabomba etc.) to work with...

Secondly, Will there be any aeration issues? If I attach a small sump (not too big! due to space constraints) and aerate the water in sump, and let the water flow in main tank gently without any surface agitation, Will the O2 and Co2 levels be ok for the tank?

Please share your insights


----------



## Michael (Jul 20, 2010)

Interesting project! I would suggest two changes. First, the soil layer should be no more than 1.5" to 2" deep to avoid severe anaerobic conditions. 

Second, provide good circulation throughout the tank with power heads, a canister filter, a sump, or some combination. If the circulation is good but without a lot of surface agitation, both O2 and CO2 levels should be OK.

If you plan on doing a sump, why not fill it with biomedia like lava rock? You probably do not need to aerate the sump, but having one with lots of biofiltration will help with any bioload problems you may have. I don't know much about arowana, but most large predatory fish do create a lot of waste, and the extra biofiltration is insurance.

Letting the tank mature for a long period is a great idea--your patience will be rewarded.

Please keep us updated.


----------



## activesize (Jun 26, 2011)

First of all, I think the first question to ask, if you haven't already given it some deep thought, is do you really want a 260 gallon NPT with only two big fish in it? In a properly functioning NPT of that size the arowana should eventually grow long and huge because the nitrates will be kept down to a low level. Eventually, the arowana could be culled, as in a backyard gamefish pond setup, and they should be good eating too. If you do that then consider using a good water treatment which will detoxify heavy metals as you add water though. However, the plants in that setup will do the job perfectly well for you too. 

Perhaps you can keep angels too with your arowanas, and some catfish and plecos too if you raise your arowanas to adulthood on a lot of bugs, ie. raise Cuban cockroaches and crickets, do field sweeps, and things like that so they grow up not recognizing other fish as food. Also, if they breed then a planted tank full of juvenile arowana would be an awesome sight, but the fry won't survive for long with angels in there. 

What type(s) of lighting will the tank have? 

Also, be sure to put appropriate plants at the ends of the tank (i.e Anacharis) to prevent the arowana from running into the sides and damaging their barbels, etc. Eventually, you'll probably need a top such as eggcrate weighed down with heavy books, or something like that too. 

As far as filtration, I would just use coarse sponge filters and eventually clean them every week or two for the first six months which will allow the plants to grow at a maximum rate while keeping the tank reasonably clean. This will allow your smaller fish to get larger too. Then, a few weeks before getting the arowana go ahead and add a good filter with lava rock biomedia because I think you're definitely going to need it when the arowana get larger.


----------



## aquabillpers (Apr 13, 2006)

There is some evidence that arowanas are best not kept with other arowanas. They can be territorial, and the largest one always wins.

In addition to eating insects from the surface, they also will eat mice, so that would be a good winter food source. I imagine that the mice have to be able to at least stay afloat until the arowana is ready to dine. There is a YouTube video that purports to show that.

Depending on the species, they can grow to be four feet long.

I like the idea of eating one that has grown too large, but from what I've read, some species taste better than others. There is a YouTube video video on that, too.

Good luck!

Bill


----------



## Wildtype Devil (Sep 23, 2011)

activesize said:


> First of all, I think the first question to ask, if you haven't already given it some deep thought, is do you really want a 260 gallon NPT with only two big fish in it? In a properly functioning NPT of that size the arowana should eventually grow long and huge because the nitrates will be kept down to a low level. Eventually, the arowana could be culled, as in a backyard gamefish pond setup, and they should be good eating too. If you do that then consider using a good water treatment which will detoxify heavy metals as you add water though. However, the plants in that setup will do the job perfectly well for you too.





> I like the idea of eating one that has grown too large, but from what I've read, some species taste better than others. There is a YouTube video video on that, too.


He he he.... nice thought!!!!	:rofl:
i think people find it difficult to eat things they give names to... though....:-k



> Also, be sure to put appropriate plants at the ends of the tank (i.e Anacharis) to prevent the arowana from running into the sides and damaging their barbels, etc. Eventually, you'll probably need a top such as eggcrate weighed down with heavy books, or something like that too.


Point noted....


----------



## Wildtype Devil (Sep 23, 2011)

Michael said:


> Interesting project! I would suggest two changes. First, the soil layer should be no more than 1.5" to 2" deep to avoid severe anaerobic conditions.
> 
> Second, provide good circulation throughout the tank with power heads, a canister filter, a sump, or some combination. If the circulation is good but without a lot of surface agitation, both O2 and CO2 levels should be OK.
> 
> ...


thanks Michael,
your advice on soil layer and good circulation is good and only logical.... (goes to my checklist:thumbsup:

I'm not pretty sure if i could go for the sump though..... serious spatial issues!!! have to plant heavily.....


----------

