He sounds precious, but if you love him as much as you say, you should
think long and hard about continuing to let him roam. Anything could happen
to him out there. The animals he kills may have ingested poison (the
rodents),
or have been exposed to dangerous nerve agents in the form of pesticides
or fungicides (insects and the snakes and lizards that eat them). Mean
people
torture cats every day, they get hit by cars (it only takes one) and stray
dogs
are a problem too.

The "be free" "we will take that chance, he LOVES the outdoors so much!"
philosophy might work fine for me up until the time I found my cat lying
under a bush with his gut ripped open by a dog or dead from being hit
by a car. It worries me to death when people allow beloved pets to roam
unsupervised.

<Reed9165@student.faytechcc.edu> wrote > We work long days and have o have a
doggy door for the dogs, but

So, you have a fenced yard, right? You would not let your dogs roam, surely?
So maybe your cat is safe after all, especially with the dogs out there too.

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Maybe rethink the open doggie door all day? How about an opening to a
shed or setting up dog houses or other forms of shelter for the dogs
during the day, and either let the cat use those too, or consider that
cats usually have no problem finding shelter under porches or whatnot.
Then just use the doggie door when you're home to supervise what comes
IN?

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Why not put the fish tank in a room where the door can be closed? If
not possible, try piling lightweight aluminum pans or other
noise-making things (I'm sure you can find a commercial training
product) on top of the tank.

While this often works to scare cats away from surfaces, yours might be
especially resistant because he's focused on getting the moving
water--plus, lots of cats love the taste of fish food. I'd rethink the
location of the tank, or I'd lock the cat out of the house during the
day.

Best wishes!