200 g. tank' currently lit with 3 MH 150 w.
Was wondering wether 4-5 T5 bulbs might be better then those MH's?
Can you explain what might be better please?

Add the T5's to the existing MH's.

Light the tank this way:

T5's=> 10-11 hours
Midday blast with the MH's=> 4 hours

Result:
Good growth, even coverage, longer MH bulb life, less heat, less potential for algae.

That's what I do on the large 350 I take care of.

Regards,
Tom Barr

Thanks Tom. The reason I ask is that I have already the MH bulbs but I got several recommendations to switch to T5 only, as it is supposed to be better, cheaper (in terms of electricity) and easier to handle (in terms of light fixtures etc).
Can you please relate to that ?
Thanks.

MH's are the most efficient method to grow plants and corals.

There's not a huge deal there, some want to make a big deal over it.
The thing that can help you: keeping the MH's and running the higher intensity for only a few hours, then allowing the T5's to give the tank enolugh light at low levels for the remainder. That will let you have the best of both worlds and some options as far as how you run the tank.

The T5 will provide low amounts and even spread. The MH's will provide high intensity.

It's hard to get a low level even spread of MH light, FL's are easy to do but not the intensity, each has a trade off.

Both gives you the benefits with out deal with the trade offs.

But it cost more, so that's the trade off...........

Regards,
Tom Barr