You have a lot of questions but you gave much more info than most newbies it makes up for it. LOL! I can't answer all your questions but there will be others along to correct that. No one pond is exactly like another and no ponder is just like another. I can't quite visualize your pond but maybe it will come clearer later on. You don't say why the pumps fail. If it is the same reason each time then I would think you should go to another type altogether. Or provide what it is lacking. If debris is damaging the pump then you need a prefilter which prevents damage to the impeller. Most pumps have a small and totally inadequate sponge in front of the impeller. Most of us toss it and install some sort of prefilter in it's place. Looking at your pump, I don't see even that, just a cap with lots of slots for water flow. Options could be change pump type, or remove filter cap and attach prefilter with sponge or other filter material. Algae is endemic when the pond gets lots of sun. You could use lots of chemicals but that is rarely satisfactory. A UV filter could work just fine by using a diverter or adding a small pump and filter. With your waterfall pump I suspect a separate pump would be easiest. More later, Sandy

I have plenty of frogs in my pond, which also contains goldfish. I seriously doubt goldfish would keep frogs away. The only threat is that goldfish eat frog eggs and tadpoles, but that's not going stop adult frogs from visiting a pond. The current tadpoles in my pond have grown large enough to be taken off the menu as fish food. I'm waiting to see if they are going to be green frogs or toads. Also, clear water and clean water are not always the same thing. A bio filter uses good bacteria to remove chemicals that can not be seen, such as ammonia.

mwp, that type of basket screen's purpose is to prevent the pump from sucking up pea gravel or anything hard that may damage the pumps impeller. The scrubbies will screen the water even further and become a small bacteria colony. It will probably require weekly cleaning, by washing it out with a blast from the garden hose. I use one in a small sump, that filters water to a pond statue that spouts water into my bog type pond/garden. I clean it about twice a season. The main pond water is drawn from the pond, through a bottom drain and surface skimmer. It then passes through a mechanical filter pad located in a 50 gallon barrel sump. I pump out the silt and other sludge from the bottom of this sump barrel once during the season and again in the fall in preperation for winter. From the sump barrel the water is pumped to a home made filter system [ Rubbermaid totes], after which it returns back into the pond via a small waterfall. The water in my ponds is crystal clear all year round. I use bird netting, pot scrubbies, furnace filter pads [the blue cut to size ones] and last, quilt batting to "fine tune" the water before it returns to the pond. My pond capacity is around 2000 imperial gallons and the filter system capacity is around 125 gallons in total. "Horton"

I just set up a small pond/water garden in a xl pot that holds about 45 gal. I am using the Pondmaster 190 and so far (2 months) I really like it. The filters are easy to clean and keeps the water nice and clear. You could leave off the top piece if you don't want the bell tower effect.