Hi Bob,

I have a 24" deep tank also over which I have suspended a Jebo 150w MH
pendant. My tank is 24"x24"x24" and as it was my first planted tank I had
to be careful wtih the light and have it about 10"-15" above the water
surface for the first 6mths whilst the tank settled to avoid algae, but it's
all good now.

Depending on the length you may want to go 2 or more. I also am starting to
regret not going for the rectangular light as opposed to the circular
pendant... I find that I am having to make sacrifices re lighting floating
plants or having more intense light to make the blyxa and rotala grow...
The round light can cast shadows in the corners of the tank when brought
down to 20cm (8" i think) above the water surface.

Hope this helps.

Justin.
wrote in message
ups.com...
I finally indulged myself in a 90 gallon, 24 inch tall acrylic tank
which I am going to move my plants and fish into once I've got all the
ancillary "stuff" that I need.

One thing I'm wondering is how much lighting I'm going to need for such
a tall tank. I'm thinking of using MH pendant lights, but I'm not sure
how many or how many watts (e.g., 3 bulbs @ 175 watts each). Any
suggestions?

Any suggestions about other issues related to a relatively tall tank
like this would be welcome.

Bob
Rancho Cucamonga, CA