80w ballast

[ThrowedToad]

I have two 80w ballasts. Pic link below. Now, these are rated for two 40w bulbs apiece. Can I take one of them and run 4 20w bulbs? This would give me the light I need in my 29 gal SW tank. I figure the other 10w is nominal, I will add a night light to the mix.lol. Is this a feasible project or not?
http://i119.photobucket.com/albums/o154/throwedtoad/S7303328.jpg http://i119.photobucket.com/albums/o154/throwedtoad/S7303330.jpg

Thank you all for your information.

 

[SpeedEuphoria]

If you wire it right so it thinks you have 2 48" bulbs it should work

 

[ccCapt]

I would not take the chance.
Go to HD or Lowes and buy the proper ballast. Probably not more than $10-$15 for a ballast.

 

[CHBGator]

That looks like an old magnetic ballast your better off buying a new instant start ballast. HD and Lowes sell them pretty cheap.

 

[jsoong]

You can only do 4x20W in an 80W ballast if it is an electronic load-sensing one. What you have is an old coil ballast. It will not work properly with anything other than 2x40.