My leaking Amp3k story:
-- Ordered pump in April, got it in May.
-- Found this post.
-- Wrote Dolphin from my personal email asking about leaking seals, never got a reply.
-- Accidentally sent Dolphin the same email from my company email, got answer in a few days saying that they did not know about any leaking problem, but had changed their spring for a start-up problem.
-- Wrote to Dolphin using my personal email, quoted their response about spring and gave them the link to this post to help them learn about the leaking issue. Never got a response.
-- Installed the pump as closed loop & huge short piping so virtually no head pressure about July 1. Within one week signs of leaking from rear seal.
-- Called Dolphin, the usual very nice response, it may stop leaking on its own as sometimes the seals seat them selves, you can send us the pump, or we can send you a seal; you will eventually need a seal anyway as it will fail eventually.
-- It maybe still leaking put is much slower.
-- They have a new pumps coming out, one with 2 inch ports (and still about 1 amp) and one that works to 27 ft with large flow rate (at about 3 amps).
It is quieter and uses less power than my Iwaki 100RLT or my 55RLT, but after 12 yrs of continuous running my I Iwakis have yet to ever leak or fail in any way. I hope they stay in business and continue this line of pumps and improve them.