Never known a ghost knife to eat flake, they prefer bloodworm, shrimp, mussel, cockle, krill. However, after much patience mine will now eat tetra prima granules, cichlid pellets and adores cucumber, never even notices flake.
you might/will find that Black knife will get way to big for your tank. They can get to half a meter long. My local LFS has just acquired one of these and he's 12" long and the bloke had only had it 6 months. I have read the minimum tank size is 400l for one of these. What size is your tank?
He will require for optimum health and growth a minimum of a 5ft tank, although fairly slow growing, they can reach 24", more likely 16" in the home aquarium, so a 240L 4ft (assuming) wont be large enough for life. However, like I said they are slow growing. Mine I got 18 months or so ago, at around 2-3", now he is 7-8". I dont know where the information that they only need 208L tank came from, but its completely inaccurate.
Also the bala sharks you bought also require a minimum of a 5ft tank preferably 6ft for life, they can reach 16" and need to be in groups. So you will need to upgrade your tank or rehome your fish at some point, the bala's will grow 1" a month with proper diet and water conditions.
It's not a case of if it gets to big, it's a case of when, because if they don't grow too big, then that's not a good sign of health - and you have no way of telling how big it could have grown given a better environment.
You should rehome them well before they get too big, to give them the best chance to grow to their potential size and live to their potential lifespan.
And when your considering what fish are suitable for you aquarium, always look at the maximum potential size. Looking at the minimum potential size is just in your best interests, not the animals, and you could end up unknowingly stunting it's growth and shortening it's lifespan .
I'll stop moaning now .
BGKF are really cool though, I'm very tempted to get one myself for my 150gal.
Never known a ghost knife to eat flake, they prefer bloodworm, shrimp, mussel, cockle, krill. However, after much patience mine will now eat tetra prima granules, cichlid pellets and adores cucumber, never even notices flake.
Mine ate literally every food that was offered to him. His fave of all was shelled frozen peas.
Mine was 14" and 9 years old when he passed I miss knifey but I wouldnt get another one, even though mine was in an 80gal (5 foot) tank he still looked cramped in there.
But yeah like I said if I get my 8ft tank I plan on building he will be shifted to there, or my friend's 8ft tank.
Considering it's only a baby at the moment and a few inches!