Seachem are very non-specific in their replies. They won't tell you to use it or not to use it in place of regular prime regardless of your aquariums size. I emailed them about what they considered a pond as the surface area of a body of water is the deciding factor for which one to use. Bear in mind they never actually state what size a body of water has to be to be considered a pond and, as such, allow the use of Pond Prime due to its surface area.
For your peace of mind, from the service agent: "Thank you for your question and for using Seachem products. Prime and Pond Prime are actually the same product but are dosed at different rates. This is due to the large surface area of a pond and the different evaporation rates. Unfortunately, you would need to treat your aquarium with the same amount of Pond Prime as you would regular Prime. Please let us know if you have any additional questions.
Product Support
1080"
The red section is where they try to steer me towards using regular prime because they know why I am asking but they did not know at that time that I had found a pond many times smaller than my aquarium. They gave some stock answer to clear them of all responsibility, i.e. do it if you want to or feel your situation warrants it, when I brought up questions regarding my tiny pond (still a pond none the less) and my aquarium/sump combo. No real help if I am honest to the questions I put to them.
The pond in my email, surface area 810sq inches, was not difficult to find and is available in most garden centres here so it is not a bizarre or obscure example of a pond. For comparison my aquarium plus sump's total surface area is 1980sq inches, considerably more than my pond example.
I would bet that most members here have tanks with surface areas and water movement many times greater than some ponds.
