Question
Dear Carlo,
I am working on building a small pond in my retaining wall with a waterfall going into it. I have a black plastic pond in the ground so far. I want it to look natural though, so I have put rocks in it, with gravel on the bottom. My husband says that if I don't leave the pond empty it will always be stinky and dirty. Leaving it empty wrecks the effect of having a natural looking pond though and I don't mind if it has some algae growing in it

Answer
Dear Susie,

If you are using the proper liner on your pond (vinyl liner) it should not be exposed to the sun light because the  ultra violet rays will reduce its life. At the same time, having stagnant water water near the house will increase the proliferation of mosquitoes.
I would recommend you using a filter and a skimmer so that the water would always be clean.
There are many suppliers of those materials and they are relatively easy to install. If you decide to use them< I can help you figure out how to do it.
Good luck, and keep in touch!

Carlo