90-gallon tank suggestions

> From: david at joshua_medimg.emory.edu (C. David Cooke)
> Date: Thu, 21 Nov 1996 16:03:25 -0500

> First, is lighting.  I have read most, if not all, of the available material
> on lighting, and for now I am planning to go with NO T-8 flourescents.  I am
> considering 8 tubes, for a total of 256 Watts, this is a little under the
> 3W/gallon rule, but wondered if it would be enough; especially considering
> that this 90 gallon is 24" high - maybe 10 would be better (boy that's a lot
> of tubes!)? 

I use 6 in a 75, which has the same footprint as the 90, and they are more
than adequate.  I beleive that the watts/gallon rule falls a little short
when dealing with T-8's, because they put out 50% more lumen/watt than
normal output fluorescents... So Maybe multiply wattage by 2/3, or better
yet, just figure out how many tubes you can comfortably fit in your hood.
I was able to fit 6 comfortably with reflectors between every pair of
tubes.  Probably 8 would be OK, 10 pushing it.

> I could go the VHO route I guess, and use 3 tubes for 330W - how
> often does one need to change VHO bulbs?  Wait until they burn out, or
> every 6 months to a year like the NO's? 

The rule with HO's and VHO's is that they put out 2x and 3x more light,
and they burn out 2x and 3x faster, respectively.  In theory, you'd have
to change your VHO's every 2 months (that is, if you're a die-hard plant
fanatic who'd change their NO bulbs every 6 months, unlike the rest of us
droogs who just wait until something burns out in one of the other tanks
before swapping tubes and buying new ones).

> That's about it, the substrate is going to be small-grain gravel, with
> laterite.  Oh, I almost forgot, I will be using CO2 injection, from a
> compressed gas cylinder - manual control for now, hopefully electronic
> control sometime in the future.  Anybody have any good plans for a CO2
> diffuser that works well in a sump?  (I haven't checked out all of the plans
> on the Krib yet :>)

I have a new drawing of my latest CO2 reactor, which is effectively a
dupla clone; acrylic tube glued to flat base with rubber feet under it,
and epoxied to PVC reducing bushings at the top.  Drip irrigation manifold
screwed into the top.  Media is a bunch of mini-balls (hey, I have a job
now, I can afford stupid things like "Minikaskade" instead of rocks). CO2
and water enter the TOP, trickle over the media, and exit the bottom
through a little hole.  Unfortunately, haven't had the time to write the
article that goes with it yet.

  - Erik

Erik D. Olson					         amazingly, at home
eriko at wrq_com