Keeping Sturgeon

I have just put two 16" diamond sturgeon in my 15ft dia x 4ft deep pond
already occupied by 18 good sized koi.

The supplier of the sturgeon was feeding them on floating koi pellets and
the sturgeon were getting their food supply from the surface where it sticks
to the sides of the pond.

Now my koi, or aptly named pond-pigs, scoff everything in sight - including
toast-n-marmite, lettuce and of course their 8mm high protein floating
pellets.

My problem is the sturgeon are a bit slow (thick) to get in on the act and I
fear that they are not getting enough food.

Last night we threw in about six large slugs which the koi usually spit out
after tasting. Are slugs sufficient for sturgeon or should I be looking for
alternative food and alternative feeding methods.?

Steve - Eastbourne U.K.
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