cwaa - regarding the tolerances on the impeller - this particular one had a 2.2mm bore and a 1.0mm stainless shaft as an axle, which ended up rattling. I started checking the impeller pumps in my "spares box" and the majority of them (mostly Rio's admittedly) had plastic bushings inserted in the ceramic that allowed for minimal play. I remember an Iwasaki I had was hard-shafted on the impeller with bearings on the caps. This dolphin didn't, but I was still impressed with the flow from such a small pump. It will have a happy life in the soon-to-be pond.
Hector - Ok, so as luck (bad? yeah, def. bad...) would have it, after reading some posts, I heard a MEOW! ARF! CRASH! GLUSH! from the bedroom. I've heard the first two before, no worries. The crash, glush, however was new, and ended up being the reactor head "removing" itself from the skimmer base. Here, I thought a) I had it tucked neatly out of the animals' reach, and b) had re-enforced the joints sufficiently. Oh well. The pump got turned off, the water shop-vac'd up and my old "test" HSA-like skimmer made from plain old white PVC
was pulled from the attic (the only REAL skimmer I've ever owned was a Visi-Jet.....), quickly sanitized and with a few plumb fittings, put back into action. It worked ok, and is still doing so now - yes, I had to drill another hole in the air inlet to stop the beckett (yup, there's in there, too!) from whistling. I've now surmised that the Mag 250 is pushing a lot more than any of the other pumps I've had on the tank. It doesn't appear that the tank inhabitants even noticed.
Since the ETS was an upgrade to what I had originally done with the HSA, I'm thinking it may be time to hit the drawing board once again. I didn't really find too much difference in the large base unit (typically ETS) and just a cap bottom (typically venturi & HSA) so I may actually just stay with the HSA. Or perhaps invent another acronym to put into my posts! The thing I liked, was integrating a small Kalk reactor into the unit, which as it turned out, was too small anyway.
I enjoy the DIY gig a lot - for those interested, and haven't found them yet, I attribute a lot of thanks in designing my HSA to the following 2 websites:
http://www.eparc.com/diy/skimmers/ian/hsa.shtml
http://www.enter.net/~reef101/faq.htm
(Ian & William, respectively). Mine's a little different, especially in the design of the beckett chamber.
As I had said, I did go the cheap route with this particular skimmer - probably $25 worth of std. PVC fittings & pipe, the beckett, and the pump. All told, $80? Downsides - I can't see it skim while the unit's screwed together. I can however, uncrew the top plug and watch the froth unfold before me. Besides, I'd much rather watch the fish! If ther's any interest, I can draw up the plans for mine - I have no trouble sharing, since it was just that that allowed me to build mine - and I think I still have some jpgs of the unit under construction.
Ok, gotta go and watch the tank!
Cheers,
Ted.
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Acronyms property of those that claim ownership, design rights property of those who claim them. I didn't invent the ETS or the HSA, however have built and designed units for non-commercial use only that may appear and may function in similar respect to said units, using assistance from those who have done same. Whew!