Good. Asian arowanas are known to have very few drop eye cases. I personally attribute this to protein-rich food. As per my observation here in China, the arowanas with DE are usually the old ones coz the owners have started neglecting them thinking it can already fend for itself. The no longer give the fish a proper nutrition. Instead they will simply tend to toss goldfish in the tansk they live in and leave it at that. However, the case is still not very much like that of silvers coz the other feeders here are also protein-rich unlike the common goldfish and rosies sold in other continents. As for black arowanas, that I do not know but there are a lot less of them in the trade, I guess, to provide a census. These are my personal opinion and is not peer reviewed so take it with a pinch of salt. Actually, there is already an article in the Ancient Fish/Arowanas made specially for this that I have researched before I got my own silver arowana. Here is the link to that article.
Are Asians legal in the US and are they the same thing as a Jardini Arowana?
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