You should really concentrate on organic search results rather then paid ads. Build your site to be seo friendly and constanstly update it with new information. Make some videos and create a blog on aquarium topics to help increase your present thru the "free search results" rather then paid. Once you get that down then move onto adwords & different ppc's.
pay pal is against the seller ........they lean to 90% buyer protection
we used to sell chameleons and talk about buyer scamming....I would never do it again