pool/pond building

[Michaela521]

Hi all I have a pool/pond in my backyard. I also have 2 live swans in there so this is a somewhat unique question. I plan on keeping water clean with chlorine and sand filter just like pools but sense the sand filter will have to deal with swan droppings I should probably oversize some.

I also have well water so to keep the water from forming scale I plan on using muriatic acid to get the ph and total alkalinity down. Testing my well water the calcium hardness is 900 ppm, total alkalinity 300ppm and the ph is 8.2

For the major question is do I have to have a bottom drain for the system to work. I having a skimmer where the water flows over a waterfall on the backside and catches all the dead leaves where there is a pump that pumps the water through the sand filter and then back to the pool.

Is that adequate for cleaning and mixing the water alright so when I add the muriatic acid it will mix evenly throughout the water. It is also 25,000 gallons. Thank you for helping