can I keep knife fish with anglefish in a 55g ??
I should think it partly depends on how many angelfish you have.
The black ghost knife will require a MUCH larger tank at adult size, like 125 gallons.
The brown knife reaches about 8 inches. 55 gallons is the minimum recommended tank size for the brown.
I have two angles at the moment, have anyone any info on the black knifefish ?
The black will not fit in your tank, as I mentioned above. http://badmanstropicalfish.com/profiles/profile66.html
Yes - they need a much bigger tank. You could grow one out in a 55, but eventually you will either have to give it up or get a big tank. As far as the knife with the angels, it's something I would do. And may do, in my 125.
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