Hello, i am a new member. I have a large tank of 150 cm with a beautiful arowana in it. The last few days he did not eat. I threw in some goldfish and hapily he ate some. I hope he becomes better, because normally he eats a lot.
You may prove what is wrong in that statement before you issue this short answer.
Goldfish don't necessarily kill the arowana but due to high level of thiaminase and fats, they can potentially block the nutrients needed by the arowana thus leading your fish to nutrient deficiency. See details here. http://www.monsterfishkeepers.com/forums/showthread.php?t=167891
to MFK by the way, Matt. Could you please post the diet you give your fish? What is the appearance of the poo? What are your water parameters? Any tankmates aside from that arowana?
One thing is for certain ...gold fish are not adding any real nutrition to your arowana ..and if the feeder fish are not your own home raised goldies then you risk disease being transmitted to the arow..from eating them and from them being in his tank water... try and get your arow on a pelleted food... then add other things such as frozen silversides and frozen krill, fresh shrimp as a treat... the sooner you get him on a varied diet the healthier and happier he will be...