Botanicals with bichirs and oscars?

[duanes]

Filters do not do anything for nitrates. You need to do water changes to keep nitrates below 20ppm. A single 10" oscar requires at least 60 gallons of water changed a week.

I agree with this, but I'm a little more anal than Rocksor....in nature riverine fish like oscars are in constant water change from flow, from the surrounding vegetation using up nutrients, and other metabolic processes.
My goal in a tank with oscars (or in any large cichlid tank for that matter) , would be to keep them healthy, and as unscarred up from HLLE as possible.
So to me, in a proper size tank, an exchange of 100% of the tanks water at least twice per week would be needed, this regime might be able to keep nitrate as close to 0 as possible (somewhere around 10 ppm).
But the smaller the tank, the faster the deleterious nutrient load builds up, for example in a 65 gal tank, with only 1 oscar, to keep nitrate at a reasonable level, a 50% water change every day, would not be overkill.

 

[esoxlucius]

Can I keep 4 oscars with length 6.5” with 1 bichir in 68 gallon tank?

Firstly, Punjabiking1500 , you've hi-jacked someone's thread with your question, you should start a thread of your own really, it just helps keep things simple. But not to worry, you're new and no doubt finding your way around, i'm sure the OP won't hold it against you!

However, your question does give me cause for concern. In reality you shouldn't even be thinking about keeping ONE oscar in that size tank, never mind FOUR and a bichir. The eventual bio load will be nigh on unmanageable, and as already mentioned, filtration, no matter how much you have, does not reduce nitrate. And oscars, who are extremely susceptible to HITH, need good quality water at all times.

I strongly advise you to follow the advice given so far, to avoid the inevitable problems that will arise if you ignore it. Your call. And welcome to the forum.

 

[Kelly_Aquatics]

Ya no problem with posting your question here no sweat but maybe post your own next time your question is quite concerning as esoxlucius said

 

[Punjabiking1500]

Please help how to post questions?

 

[Kelly_Aquatics]

go to the new posts section and click on the post a thread tab select your subforum and then write your thread