How Can I Raise & Lower Water Level In A Plumbed Tank

If I wanted to set up a tank where I can easily raise and lower the water level in the tank while using a wet/dry or sump filtration system, how could I accomplish this?

I have figured out two ways so far:
1) Drill multiple holes vertically and install ball valves to regulate which hole the water will drain out of.
2) Install a stand pipe that I can rotate downwards to affect where the water level is, the top of the standpipe will dictate the water level.

If I had to choose one of these I would choose option #1 but wanted to see if there were any other options before making my tanks look like swiss cheese.

Thanks!

Thanks for the reply but if I was going to do it this way I think it'd be easier to go with my option number 2.

Any other ideas?

Yes I mean raise and lower water level in the tank itself.

The holes can be drilled anywhere vertically along the tank wall so that you can choose which hole to have the water drain out from by opening and closing a ball valve. Depending on which hole you have open will dictate your water level.