<a href=showthread.php?s=&postid=7543570#post7543570 target=_blank>Originally posted</a> by FLIPbmw
First off, what do you plan on keeping?
Secondly, give it a shot and let us know how it works out for you. If you read around, people say to stick a 4Tek light on a 75g and it will be ok, then if you check at 40 breeder posts, people mention to also put a Tek 4 lamp, but if possible get a tek 6.
The 40 breeder is only 16" with a width of 18".
If you plan out how much the unit would cost you to run over the years, you might save a bit.
From what people say, a T5 with a parabolic reflector will work 2x better than a plain reflector.
You could get by with 4 bulbs with good reflectors. Factor in energy bills, and bulb replacement.
If $Bulbs = $Reflector, then after the first initial change of the bulbs, you would be saving money on replacement parts after, and save energy.
Pros to a 4set w/good reflec:
Save $ replacing 4 less bulbs
Save $ running 4 less bulbs
Save 'space' but to each his own for putting a value to that
Cons:
Limited bulb mix and matching, ie; 4bulbs vs 8 bulbs
Might leave the top edge of the tank darker due to spacing of the bulbs (if all the bulbs are towards the center, there will be dark areas near the top but not affecting corals since it is out of the way).
I have T5 Normal outputs on my 40 breeder. 2x10,000k, 2xActinic. Progress at the moment, even tho it is cycling, I have seen quick growth of my GSP frags. And I have a flat reflelctor.
Personally it depends on what you want to stick inside. IMO The more bulbs the better, but you will be paying for it in the long run and 8 is plenty, probobly even too much.