Is My 250w Mh Really Needed

[jeasko]

As my 250w lamp looks like its on its way out (premature failure!) I happen to have a 150w ballast, cap, lamp and lamp holder which im considering changin over to, but im not overly sure its powerful enough as my tank is 39x18x18.

So before I start taking it apart and changing all the gear over I thought id ask the question here.

oh the tank has hardies and softies in it along with a derasa clam which is why i went with the 250w to start with

your comment would be greatfully received on this

 

[SkiFletch]

Ummm, I doubt it would be enough... You'd have to move the corals in towards the center and up in the rockwork for this to work.

How do you know your 250 is dying?

 

[jeasko]

it seems its not dying now, but think it was trying hot re strike (not sure the unit was cooling enough after a minor power blip) which these things really dislike, the tube was acting very strange so am looking into changing the lamp anyway now, the 150w gear etc I have is only a stand by really but wasnt sure it would be sufficient for a long period of time.

so panic over

 

[SkiFletch]

Ah yes, the hot restrike always does freak people out. Figured it was somethin like that as Halide ballasts rarely fail that soon

 

[pleder]

Are the dimensions of the tank in inches? Your going to get some heavy fading areas around the sides of the tank. Should start fading off 6 inches or so from the sides so maybe put the less light demanding corals there.

IME a 150w will penetrate 18" though.

HTH