I'm setting up a new 65 gallon tank. I'm planning to keep Gar, Snakehead, Mono, Arowana, Oscar & Wolf. Any ideas or suggestions about the mix?

Woah - that's a pretty big load for only a 65 gallon tank. In my head I feel that one lone Oscar fills the bioload limit for just a 55 gallon. Adding all of those into a 65 gallon mix is going to be a whole heck of a lot. Plus when everyone is fully grown it'll be cramped to an extreme.

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I like big fish tanks and I can not lie. You other brothers can't deny.

They are all babies, nothing more than 4 inches. Beside I can move some of them to other tanks later on, but I just need to know if its ok to mix the those species together or not.

Well yeah, you can most likely house them all together as babies. But when one of them gets a growth spurt while the others are lagging behind then things might go awry.

In all honesty though I wouldn't house them as babies just to expand and place them else where as they grow. Essentially, with these fish, you'll then be looking at a separate 55 gallon (minimum) for each of them including filters, heaters and the whole shebang. My pocket book would cry silently each night knowing what's in store for it when the babies get too big, hahaha.

And scratch that on them all living together - if that Mono is the "finger fish" mono that I'm thinking of then no - it needs brackish water and shouldn't be housed with the others.

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I like big fish tanks and I can not lie. You other brothers can't deny.

wolf fish is a mean sucker, also snakehead is illegal in most states might wanna look into that if ya havent, i really wouldnt recommend doing this either seems like a bad idea

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Tank
125g african cichlids making it work
75g rimless Reef in progress

last I knew, snakeheads were illegal in the U.S.

and when its big enough it will eat everything else in the tank.

I'm in Dubai, Nothing is illegal here. It costs USD 190 to set up a nice 65 gallon aquarium here, so cost is not a problem, the fish are very cheap too. Gar is USD 9 each, same for Snakehead & Mono. I've seen Mono live more than 10 years in a normal freshwater aquarium with other fish without any problem.

Well good luck in this land of the free then. Illegal or not, as pointed out a snake head just is a bad tank mate.

Also that mono that lived in freshwater for ten years was probably pissed off and never fully thriving. You yourself could live at the north pole if needed but you would probably hate every minute of it as it isn't where you are from or the weather you are used to.

You came to here asking for advice on the set up you want. As pointed out it is a bad idea. The fish are not compatible or will become incompatible shortly. Also the mono does require brackish water to thrive. If you wish not to heed advice and you have your mind set then by all means do what you want.

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I like big fish tanks and I can not lie. You other brothers can't deny.

Monos are at their best in brackish water. They are also a schooling fish so should be kept as a group.

Most fish do their fastest growing in the first 6 months so you could be looking at multiple tanks in a very short time. If you have the space time and money to invest then you can afford to experiment but just remember even at the prices you say you could be looking at investing 1000 dollars in the next year to properly home all the fish.

Instead of getting so many fish consider choosing your favorite fish and building the tank around it. Take your time to choose the best decor, conditions and any possible tank mates. You will find it more rewarding and interesting in the end and the fish will have the best conditions possible. If you want a lot of fish in a tank you need to be looking at a different type of fish that are suitable for a community tank.

I know you guys are trying to give me some good advice here. Credit given for that, but when i watch those videos in you tube and ask the owner about the mix, it just makes me confused again !! Most say its fine to keep the mix I mentioned as long as there is enough room for them. I'm easily convinced if you tell me something based from your own experience or scientifically proved.

Lets say, I'll just have Gar, Snakehead and Wolf, is this mix ok or still there is a chance of attacking each other?

There will always be a risk of them attacking each other as that is just in their nature.

The biggest reason the fish in the youtube videos are getting along so to speak is because each fish is cramped to an extreme. With no room to mark territories the fish usually just give up and deal with each others presence. The problem with doing that is that you have an enormous bioload that you have to attend to and your fish will not be at 100%. Also come feeding time in such confined spaces leaves little room for snappibng jaws and other fish will get in the way.

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I like big fish tanks and I can not lie. You other brothers can't deny.

Ok, I can go for a bigger tank, I saw this nice one the other day which was 3.3 feet long, 2 feet high and 1.5 foot wide.

Most people recommend that a single Arowana requires a 250 gallon tank MINIMUM. Just so ya know.

I personally would keep your favorite of the species you have mentioned and get the right sized tank for that fish.

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I can understand how it is confusing. People do things different ways and one way might be not always be better than another but remember just because some kid posts a video on youtube of fish he's had for a few months or even a couple of years and says they are doing well doesn't really mean a lot. Keeping fish alive short term and For example Silver Arowana grow to 30"+ should live at least 15 years.