Re: lighting

["Wayne Jones" <waj at mnsi_net>]

Madan Subramanian wrote:

We do get NO T8 and T 12s, 2 ' and 4' Fluorescents. Their wattage is 36W
for
a T8 and 40 W for a T12.

I reply:

You should be able to get enough light with the T8 lamps if you put
enough of them. That type of lamp is probably not best suited for
overdriving but it will work. I wouldn't do it if the lamps unless the
lamps are very inexpensive. It is pointless to make reflectors for these
lamps in a deep tank as there is not enough room but it really helps to
have a difuse highly reflective surface behind the lamps. Specular
reflectors for this application are a scam.

Madan Subramanian wrote:

The best I have found is Philips Trulite T8, 6500K. My plants did really
well except for the forground plants like Tellennus and Lileopsis. Their
growth was slooow in a tank 21 inches high. I did use electronic
ballasts
with a factor of 1.05 the results were still the same.

VHO lamps I have not
been able to find here.

I reply:

I wouldn't look for them either. You have something better already.

Madan Subramanian wrote:

Also available are Philips PL-L/85s 36 W power compacts at 6500 K, even
with
these the growth was marginally better. I have not been able to find
reflectors - the kind you see in the TFH ads for 4' Fluorescents.
I did find excellent reflectors for the Philips PL-L/85s, but the
reflectors
were shaped in such a way that the light would get concentrated and not
spread out. You needed 4 of these bulbs and reflectors for a 3 x 2 x 2
feet
tank or you would end up with dark areas. Plants did well but there was
the
question of that elusive lush forground.

I reply:

I would have thought that the PL-Ls with reflectors would have worked
especially as they concentrate the light just as a MH would. Just put
the lamps over the foreground plants.

Madan Subramanian wrote:

Then I got my MH and converted my tanks to open top. One single
Tellennus
plantlet that grew into about 10 in 18 months exploded and I have a
great
foreground now. All things considered I find MH lighting the best for
tanks
2' in height and for tanks of 20" depth there needs to be some planning
and
DIY with regard to lighting in order to ensure you get a good
foreground.
You have to get the lighting right first before you can setup your tank
and
the wait is very frustrating. I am not obsessed with forground plants
but
getting them to grow has been a challenge for me.

I reply:

Tennelus is not a very light demanding plant. It will actually grow for
me at the bottom of a 2' tank in what would be called a medium light
tank. It is pretty sparse though. In my high light 2' deep tank it grows
no problem at all. This is with T8 lamps similar to your 36 watt T8
lamps driven to about the same light level per lamp and spaced just less
than 3" center to center. The distance from the water surface to the
substrate is 20".

Wayne