Will Oscars pair at High PH?

[Fishworks2015]

Hi Monster Fish Keepers,

Just wondering if Oscar fishes will still pair off even when water parameters are not optimal?
My pH is 8.1, kH is 4, gH is 4. pH is High but Hardness is quite low.

I ask because I want to keep 6 Oscars and absolutely do not want them pairing off.

My original plan was to buy a dozen of juvenile oscars, grow them, get them to spawn, vent sex them, and then just keep all males.
But if they wont pair off, then I can keep the 6 Oscars in a mixed gender environment.

Thanks!

 

[duanes]

Over the > hundred years they have been kept, when oscars got too big for tanks, people released them into Lake Gatun here in Panama, and they have become a very common invasive resident .
The pH of Lake Gatun often rises to 9.
Obviously they have spawned, and successfully, although its anybodies guess how many generations have succumbed to the ravages of a being released in a less than perfect environment before those that could adapt became the successful population living in the lake today,
Perhaps millions died, perhaps millions were scarred with HITH before adapting the resistance to aberrant conditions.
Same goes for the lakes population of invasive Cichla.
It is well known although the lake is full of P bass, they only reach about 2/3 the size of those in the soft, low pH waters of the Amazon region.

 

[Fishworks2015]

Over the > hundred years they have been kept, when oscars got too big for tanks, people released them into Lake Gatun here in Panama, and they have become a very common invasive resident .
The pH of Lake Gatun often rises to 9.
Obviously they have spawned, and successfully, although its anybodies guess how many generations have succumbed to the ravages of a being released in a less than perfect environment before those that could adapt became the successful population living in the lake today,
Perhaps millions died, perhaps millions were scarred with HITH before adapting the resistance to aberrant conditions.
Same goes for the lakes population of invasive Cichla.
It well know although the lake is full of P bass, but they only reach about 1/3 the size of those in the soft, low pH waters of the Amazon region.

That is quite surprising info. Please allow me to reiterate.
So since Oscars have successfully spawned in Lake Gatun with a pH of 9, the Oscars in my home aquarium with a pH of 8.1 should be able to lay eggs at least?

Also, I promise not to let any of the next generation Oscars loose into the wild. I am not really looking into breeding. Just wanting to have a handful and enjoy them for myself in home aquaria for their lifespan.

Thanks!

 

[Fishworks2015]

Over the > hundred years they have been kept, when oscars got too big for tanks, people released them into Lake Gatun here in Panama, and they have become a very common invasive resident .
The pH of Lake Gatun often rises to 9.
Obviously they have spawned, and successfully, although its anybodies guess how many generations have succumbed to the ravages of a being released in a less than perfect environment before those that could adapt became the successful population living in the lake today,
Perhaps millions died, perhaps millions were scarred with HITH before adapting the resistance to aberrant conditions.
Same goes for the lakes population of invasive Cichla.
It well know although the lake is full of P bass, but they only reach about 2/3 the size of those in the soft, low pH waters of the Amazon region.

Actually, I know I should not release any Oscars into the wild at all. Not any of the ones I get initially or the offsprings.

 

[tlindsey]

The Oscars in my home aquarium with a pH of 8.1 should be able to lay eggs at least?

Yes

 

[tlindsey]

Yes

I personally would just by 6 small Oscar and watch them grow. It takes years for Oscars to mature and breed unlike most Cichlid.

 

[duanes]

I agree with tlindsey.
My point in posting about the oscars now adapted to lake Gatun, is to illustrate that it took many generations (perhaps 50 or more years), and presumably many deaths of oscarsfor them to evolve the ability to to thrive in lake Gatun's hard, high pH water.
Trying to adapt S American soft water species in one or 2 generations to hard water, is probably not going to be very successful.
If you were able to access progeny from Lake Gatun's hard water population, this would be a different story.
Or if you were able to access progeny that have been living in a Florida hard water lake, or bred by someone with hard tap water for the last 50 years, that may also work.
Or if you are willing set up a RO/DI system that reduces TDS, and pH.
Otherwise, expect in 2 years or so, your oscars to be scarred up with HITH, unless you are willing to do daily fin level water changes, that reduce the chemical stress of high nitrate and the HITH precursors (that compound the stress of high pH water)
.....in most cases.....successful breeders adhere to the basic natural needs of fish they keep, with the above measures.
With your pH 8.2 tap water, (If it were me) I would choose some other cichlid (native to Mexico, Central America, or the African rift lakes) that thrive in your type water, instead of fighting mother nature.

 

[Fishworks2015]

I agree with tlindsey.
My point in posting about the oscars now adapted to lake Gatun, is to illustrate that it took many generations (perhaps 50 or more years), and presumably many deaths of oscarsfor them to evolve the ability to to thrive in lake Gatun's hard, high pH water.
Trying to adapt S American soft water species in one or 2 generations to hard water, is probably not going to be very successful.
If you were able to access progeny from Lake Gatun's hard water population, this would be a different story.
Or if you were able to access progeny that have been living in a Florida hard water lake, or bred by someone with hard tap water for the last 50 years, that may also work.
Or if you are willing set up a RO/DI system that reduces TDS, and pH.
Otherwise, expect in 2 years or so, your oscars to be scarred up with HITH, unless you are willing to do daily fin level water changes, that reduce the chemical stress of high nitrate and the HITH precursors (that compound the stress of high pH water)
.....in most cases.....successful breeders adhere to the basic natural needs of fish they keep, with the above measures.
With your pH 8.2 tap water, (If it were me) I would choose some other cichlid (native to Mexico, Central America, or the African rift lakes) that thrive in your type water, instead of fighting mother nature.

So you recommend just getting the 6 young Oscars and watch them grow? Down the road, let them pair then just rehome the others?
Keeping nitrates at 20ppm max would work with keeping Oscars?
Can you recommend other cichlids for high pH? I will visit some LFS and see about my options.

 

[duanes]

There are about 2,000 species of cichlids in the world.
Any cichlid from Mexico, and Central America is from water like yours, as are any cichlids from the African rift lakes (there are about 600 species from the rift lakes alone.
I believe even 20 ppm nitrates are chronic disease producing levels for soft water cichlids like oscars, when in combination with hard, high pH water.
By doing frequent water changes, I try to keep my tanks in the 5 ppm levels or lower.
Below are a few cichlids that would appreciate your type water.

Above Cincelichthys bocourti, from Mexico and CA, below Ctenochromis horei from Africa


Above Vieja breidhori, below Herichthys carpintus, both from Mexico


Above Nimbochromis livingstoni from the African rift Lake
Below Parachromis motaguense from Mexico

All the above, and many more, are high pH, hard water loving cichlids

 

[Fishworks2015]

Duane,

Its been real hard finding fish in this Virus situation. I hope you and this community has had a chance to get vaccinated.

One LFS I found has some Peacocks, Eyebiters, Yellow labs and Demasoni from Lake Malawi. Will probably try the Yellow labs with Demasonis sometime hopefully this year. I am going to start with a 36"x 18"x 18" (50 gallons) with a canister filter. Hardscape will be white marble sand with dragonstone. I will try to stock with 4 yellow labs and 16 demasonis. Hopefully they lay eggs and I can vent sex them later to get a ratio of 1m:3f.

I will try to do your standard of 5ppm Nitrates as well, it's nice to have standards.


Currently reading your rant from 2019 titled "Whats the big deal about soft water cichlids in hard water". Still not done reading, am on page 9.
Intrigued by the idea that fishes can adapt and evolve.. although as you said, who knows how long before Oscars adapted to Lake Gatun.
At the moment, I don't know if I am a proponent of "just clean water is all we need".
I could have easily been one of those people, 3 years down the road having Oscars with HLLE scars. I am fairly new to this hobby. Only experience I have is 4 months with 20 Cardinal Tetra, then I had to give them away to a friend because of my work and travel. They were and still are in good shape thankfully. Aside from that, I like to research on the net about proper aquarium husbandry and ofcourse beautiful specimens.


I had a thought today about keeping a medium sized tank, some volume where I can perform daily water changes without restraint, dimensions 8'x3'x2'( 360 gallons + a sump). Also, understocking the tank to really thin out those Nitrates. Then I could possibly succeed with soft-water cichlids in higher pH.
If I push through with soft-water fishes, I know I am stretching the fish out, but I really like the way they look (to me its subtle beauty), but I would at least try to do it responsibly, humanely and sustainably.

Today, I saw some Rotkeil Severum (red shoulder severum) and Thorickthys Ellioti (spot-cheek cichlid) at the LFS which I thought I might try out instead of the Oscars. They are of smaller size and I believe a lighter bio-load. Also, I read these guys are quite adaptable.
Do you think I could get them to spawn atleast in the proposed 360g?