New World Large Aggressive Community tank

[Hedrus]

What is your end goal for the arowana? Is this a fish you wish to keep 10 years and over? Or is it merely to have and then rehome after a year or 2? Yes they can get bigger than 36" in the aquarium see pictures below of a captive silver, that didn't have the best care in the beginning, and yet still hit 40" (not completely straight in picture).

My silver arowana in 4500 gal

Our arowana bad streak goes on. In the last year we had lost two big old ones, Delray and Fre, and now the relative newcomer Falcorina has died at 30 inches at probably 2.5 years old. We got her less than a year ago. At present I believe this is just a coincidence and no common cause can I...

www.monsterfishkeepers.com

Again I am just doing research. I finally found a few videos that actually do some real talk about what is needed. Ideal tank scenarios for an arowana are pretty extreme. I would suspect many peoples homes aren't even equipped for the weight of a tank that is around 2000 gallons. 12 feet x 4 feet x whatever is going to be way too massive. I guess if I lived in Florida and had a huge greenhouse I could have a pond inside it that was that size. Arowanas are out. A tank that size would actually be dangerous. Not to mention incredibly expensive and extremely hard to maintain. So I assume literally 99% of everyone keeping arowanas are keeping them in way too small tanks. All articles I have read say 250 gallon which is laughable in comparison to 3x body length for tank length and 1.2 body length for tank depth. 1500-2000 gallons. Thats a factor of almost 10 off from what articles are saying. Something doesn't add up and an arowana is cool but not that cool. I still have yet to find a single article that talks in real numbers about arowanas. Moving along back to my original plan minus arowana.

To be clear about what I am actually excited about- Oscars were what got me wanting to do this. Reading about potential tank mates for them and just my preferences on what I think look interesting and aesthetically pleasing I came up with the list I made. I'd rather not do the Quetzal if that is the only fish in my list that requires other conditions. And I know I said a paragraph above that articles are ridiculous(ir arowana 250 gal) but what I made my list with was based off of articles from the same sites that say arowanas only need 250 gallons. I'm trying to be realistic. The fish I picked were from the list of Oscar community tank ideas. They were the fish I liked. My personal problem is there are a lot of fish I actually don't like or don't want to keep. If I'm going to do this(and for me this is a pretty big commitment I don't take lightly) I want to do it the way that I will be happiest with.

To recap new revised fish list-2 Oscars(reason for doing this), Red head Severum(number up for discussion), 1 green terror(I love these guys), Red Hook silver dollars 5-10, Clown loach 5, 1 large pleco. If this list can work with a roughly 300 gallon tank I would be super happy with this. I am looking for best tank size for these numbers. Or if this is totally crazy like the articles about arowanas. There is a lot of bad info out there. Is there another fish that kind of looks like a quetzal that would work with this idea? I was thinking flowerhorn(which looks similar) but they seem way too agressive even for this tank idea. I was thinking I'd get a flowerhorn specific tank later if I really wanted one. I love the pink/red and blues and oranges the quetzals have. I also love their body shape. Thanks again to everyone that has commented. I feel staggeringly lacking in knowledge here. Trying to catch up but the internet so far isn't the best of help.

 

[Hedrus]

Also, sorry for the word salad responses. I'm always doing this late night after work. Hopefully what I am typing is understandable enough to convey my thoughts.

 

[Rocksor]

Also, sorry for the word salad responses. I'm always doing this late night after work. Hopefully what I am typing is understandable enough to convey my thoughts.

Just don't use the water from the water softener. I have seen too many issues with folks in my area using water from the water softener for their fish tanks. Over a period of months the fish start to decline, whether they are hard water fish or soft water fish. Your GT will thrive in your water.

I would skip the red hooks, and opt for something smaller like the common silver dollar (only the size of your palm). When you put silver dollar types in schools 10+, they act way different than a school of 6. In a school of 6, they spread themselves out in a large 8 foot area, and stake out their territory. Larger numbers, and they swim around more and bicker amongst themselves. That being said, SD types made my oscars and other fish jumpy whenever they saw movement outside of the tank. When I removed them, the fish were more pet like, and were no longer skittish. Also, I noticed the bioload of 5 was almost equal to a 8-10" size cichlid due to their ravenous eating nature (plus pooping afterwards). I saw a significant drop in nitrates removing my school. With clown loaches, unless you spend the money to get them large ($20-$30 ea), there is a high chance an oscar will attempt to eat them and them then you are left with 2 dead fish since the spike under the CL eye can kill the oscar while in its throat.

A very mellow cichlid but great in your hard water is the pearsei (similar body shape as the melanura that you wanted). DMD123 can vouch for their similar personality. With a smaller mouth you don't have to worry about smaller fish like CLs. It's more herbivorous than the oscar. Here's one of his threads

H. Pearsei growth question

I have had 'Porkchop' the Pearsei since October 2012 when I got it at 5". I have read that these guys even though large dont really sexually mature until like 3yrs old. Dont know how true that is but in the time Ive had mine it has grown quickly but seems to be stuck at the 12" mark for some...

www.monsterfishkeepers.com

A cousin of the pearsei is the bocourti is another option. If you want something a tad bit smaller there's the Oscura heterospila.

 

[dhop2210]

I have a tank with 2 oscars, 1 GT, 1 Pleco and 4 silver dollars and they all get along pretty well. Definitely need to make sure the tank is well maintained with proper filtration and consistent water changes, but so worth it in the end.

 

[Hedrus]

Just don't use the water from the water softener. I have seen too many issues with folks in my area using water from the water softener for their fish tanks. Over a period of months the fish start to decline, whether they are hard water fish or soft water fish. Your GT will thrive in your water.

I would skip the red hooks, and opt for something smaller like the common silver dollar (only the size of your palm). When you put silver dollar types in schools 10+, they act way different than a school of 6. In a school of 6, they spread themselves out in a large 8 foot area, and stake out their territory. Larger numbers, and they swim around more and bicker amongst themselves. That being said, SD types made my oscars and other fish jumpy whenever they saw movement outside of the tank. When I removed them, the fish were more pet like, and were no longer skittish. Also, I noticed the bioload of 5 was almost equal to a 8-10" size cichlid due to their ravenous eating nature (plus pooping afterwards). I saw a significant drop in nitrates removing my school. With clown loaches, unless you spend the money to get them large ($20-$30 ea), there is a high chance an oscar will attempt to eat them and them then you are left with 2 dead fish since the spike under the CL eye can kill the oscar while in its throat.

A very mellow cichlid but great in your hard water is the pearsei (similar body shape as the melanura that you wanted). DMD123 can vouch for their similar personality. With a smaller mouth you don't have to worry about smaller fish like CLs. It's more herbivorous than the oscar. Here's one of his threads

H. Pearsei growth question

I have had 'Porkchop' the Pearsei since October 2012 when I got it at 5". I have read that these guys even though large dont really sexually mature until like 3yrs old. Dont know how true that is but in the time Ive had mine it has grown quickly but seems to be stuck at the 12" mark for some...

www.monsterfishkeepers.com

A cousin of the pearsei is the bocourti is another option. If you want something a tad bit smaller there's the Oscura heterospila.

Thanks so much! This is exactly the info I am trying to collect. No one has mentioned anywhere in my reading or watching videos about Loaches being dangerous if attempted to be eaten. Or that Silver Dollars can impact the larger cichlids behavior in a bad way. The more I research the more I am leaning larger than 300 gallons. I think 500 is my limit. Somewhere in between there. I want maximum flexibility. I added silver dollars to my list just for some variety and distraction from aggression. But if they add a huge bioload and aren't really worth it I can skip them. Same goes for loaches. Just variety in body shape and behavior.

I do really like the pearsei, bocourti and Oscura heterospila. All 3 are nice looking and do have a nice body shape. In general are most of these fish very sexually dimorphic? In color or body shape? I know some of the fish I have been researching are. Should I try to get sexed specimens of a specific gender or does it matter? I'm actually shocked at how cheap fresh water fish are for the most part. I've never attempted to do a large tank with salt water(anything over 150 gallons) because of how expensive the fish are.

 

[Rocksor]

The main consistent traits for sexual dimorphism is head hump and breeding dress for most Central Americans. (Oscars do not have sexual dimorphism until the egg laying and fertilization process occurs). Having opposite sexes can cause territorial issues when a pair get bonded, which can happen even across differing species. If you want a breeding pair, do not force the pairing, get 6-8 juvenile and let them pair naturally (rehoming the ones you don’t want). Another tactic is only keeping all the same sex. With a 300-500g, you have a lot of options for simply growing out groups (eg from1-3”) and rehoming along the way.

 

[Toby_H]

In my experience, most fish that have been tank bred for multiple generations are not very restrictive in regards to their native water parameters. Provided you don't push that to extremes. FYI, F1 are captive born of wild parents, F2 are captive born of wild grandparents, etc.

If you are simply building a large aquarium around Oscars, you really do have a lot of options. Keep reading articles and asking questions.

One of three things will limit your stocking: 1. Physical tank size (ruling our the arrowana basically removes this concern, 2. Aggressive, 3. Water quality / waste build up.

If you add some of the more aggressive fish you've considered, aggression will be your ceiling. If you stick to more docile options, it will be water quality / waste build up. The great thing about Oscars is they are big enough to hope their own with many more aggressive fish, but they are docile enough that they usually don't pick on mid sized tankmates (note: usually).

Another thing to consider is the gender of the fish you choose. Green Terror for example, a healthy male can get 10", be a very capable fighter and territorial. A typical female will be around 6" and fairly docile (when not breeding).

In my personal experience, I prefer lots of less aggressive fish mixed together, or a breeding pair of a single species in an aquarium.

From what I've read, it seems you'd prefer the "lots of less aggressive fish" approach.

In an 8' tank you could fit a few Oscars. They primarily stay in the "open water" in the upper portion of the tank.

I'd encourage you to check out a few Geophagus species. They are "Earth Eaters" meaning they sift through the sand all day eating scraps. Very helpful in an Oscar tank. They do best in groups, a few males and a bunch of females. They are rarely aggressive outside of their group.

Severums, which you mentioned, fit perfect here. They're good sized but aggression is moderate.

The Green Terror is more aggressive, but as mentioned a female would likely be okay.

There are a lot of other medium sized Cichlids that don't get nearly the fame they deserve. Keyhole Cichlids, Rainbow Cichlids, Firemouth, Acaras.