Re: MH Lighting

> From:  (Dirk)
> I recently saw an ad for a company selling 175watt MH "retrofit" kits for
> $75US.  Included is socket, mounting bracket, cord, plug, lamp and ballast,
> and a one-year guarantee.  On a watt-per-dollar analysis, this would seem
> much cheaper than a fluorescent setup with electronic ballasts, etc.  Two
> of these would produce more than 4.5 watts per gallon for a 75gal tank, and
> would make for a hood much easier to construct than one containing, say,
> fl. tubes.  Where is my logic wrong here and what questions/issues should I
> be considering?

If you build a hood, it needs to be large enough and should have provision
for ventilation. I prefer the pendant design with a large parabolic
reflector (same as the kind used for industrial lighting, football fields..)
The numbers you quote sound accurate for price. Remember that for a 
product to be profitable, the retail price is often 200-400% of the
cost of materials and assembly.

> P.S.  Just wondering. . . .  If PMDD ought, ideally, to be refrigerated and
> kept in darkness, why don't the commercial products have to be . . . or
> should they be and the companies just aren't telling us?
They may contain preservatives, in particular, I think HCl was mentioned.
Flourish has a label indicating it should be refrigerated after opening.
Makes sense, eh? A concern would be to ensure kids don't drink it by
mistake. Quite poisonous I expect.

Steve Pushak      spush at hcsd_hac.com     Vancouver BC Canada