Question
Hi Jonathan
Just a couple of questions regarding my pond which ive just built its about 1000 gals biofilter, waterfall and uv plus 4 koi water cemistry all within limits.
ok now of the questions.
1 Do you recommended snails
2 I'm going to buy a heater to stop my pond from freezing do i put it before the filter or after.
cheers
Geoff

Answer
I would say "NO!" to snails. They can be beneficial to a pond, but may quickly try to inhabit your yard.  I know people who hit snails with the blade every time they mow their lawn.

There are 3 types of heaters.
1) "In-line" heater, like a swimming pool's (I believe this is the type you are considering)
2) Floating de-icer
3) In-pond elements

If you're just trying to do right by your fish, a floating de-icer is all you need.

If you wish to keep tropical fish in your outdoor pond, go with the in-line heater.  If you get an appropriately sized one, it should cost about $1,500-$2,500.  It shouldn't matter where you put it because ALL the water will be heated evenly (if you observe the recommended watts/gallon/hour rate).  For safety reasons, make it the last item in your line.

As long as the water near the in-pond elements is being moved around, the heat will be evenly dispersed too.  Unless you are keeping breeds of fish in your pond that aren't normally kept outdoors in your area, these are perhaps the best option.  You'll save some cash too.