Melanotaenia praecox

[ArmandoNvs]

Interesting that some sites/people say Melanotaenia praecox do better in harder, alkaline water, while other people say they prefer and do better in acidic water.

What would be the right answer?

Edited January 14 by ArmandoNvs

[Tony s]

I have had them in 12dgh , 8dkh water and they did fine. Now have them in remineralized ro water at 7-8 dgh water with 4dkh water. Same fish. Seemed to do fine either way. Approaching 2 year’s old for them. Appear to be very tough animals. When I was starting to learn ro water I was remineralizing top off water as well, and my dgh was climbing until I figured it out. dgh ended up at 16. And they’re still here with no loses. 
 

Edited January 14 by Tony s

[Tony s]

Now, if they’re wild caught, you’re going to need to match their native water. If they’re tank raised, match the tank source water. At least to start 

So for the ph, if they come from wild in soft water you’ll need a lower ph. Tank raised are usually going to be higher. Depending on source. Chicago is going to be around 7.7-8.5. Parts of west coast and east coast going to be around 6.5. They will do fine in either and will adapt. Better than trying to hit a certain ph would be to use your own tap water and give them a consistent source of water and ph level. These guys are not like discus, they will adapt fine. Consistency is key 

Edited January 14 by Tony s

[Mmiller2001]

I keep mine in 5.2dGH and near 0dKH and pH of 5.0. Tank bred.