I moved into a new house about 5 months ago. Its located on ten acres and i plan on moving our horses over in the next year or two.

The well driller put in a pump that is not giving me the gpm i will need now and in the future. I think my current gpm is around 5-6 gpm.

Here are my well specs:
Yield = 20 gpm
Well Diameter = 6"
Depth of Pump = 75'
Well Depth = 120'
Casing Depth = 72'
Static Water Level = 25'

Here is a breakdown of water requirements for the house:
4 bathrooms - 4 toilets, 6 Faucets, 3 bath/shower,
Master Shower (INCLUDES 6 Grohe Fixtures - rated at 2.5 gpm each)
4 outside spigots
4 Faucets (this doesn't include bathroom fixtures)
Eventually i will be irrigating the lawn and horse dressage arena

Since i know i need to switch my current submersible pump and water pressure tank to handle more flow, I want to make sure i make the right decision when getting a new pump.

I had one plumber tell me to get a Goulds constant pressure well pump (he said that would eliminate the pressure tank). Reading through various plumber forums i wasn't sure what to make of these pumps... The plumber that did the work on this house told me to get a bigger pump and pressure tank for around $2000 (which seems kind of high).

What should i get -- a bigger pressure tank and pump, or should i go with a constant pressure pump?

Thanks for your help and advice.