i just replaced my 2 250watt mh
with the ushio bulbs on my 75, and WOW what a difference. much more light, whiter light 10,000k bulbs. these bulbs are twice as heavy as the factory bulbs. sweet. got them on ebay 68.00 apiece. any where else99.00-119.00. i got the M58 ballast, which is a core and coil ballast with a probe start. A to T LAMPS.
8) on the under side of your ballast it should give you a code.
75gal oceanic with 20 gal refugium, 750g.p.h.pump for HSA-250 skimmer, EHEIM-1250 PUMP FOR 200gph mincal. calcium reactor with 20lb co2 tank and co2 regulator with solenoid, 800G.P.H. overflow box pump and filter, aquaclearl 500 power filter for circulation and carbon use only,wave maker 900, 3x300g.p.h., pinpoint ph controller, delta star 1/3hp chiller.with 600g.p.h. pump, spectrapure automatic liquid level controller for the addition of ro.di.top off water, kent marine 4 stage delux maxxima 35g.p.d. hi-s, t.d.s. monitor, flush kit, 170lbs live rock, 5in sand bed, acropora's LG green,pink, and med purple, LG montipora encrusting purple, LG porities coral yellow, LG ruffled ridge coral, LG starburst coral green, green hairy mushrooms 100+, blue mushrooms, red mush, fluorescent green mush,green striped mush, bubble coral, LG finger leather and 2in baby, green ricordia mush, in refugium halimeda plant, caulerpa, and lot's of bug's. 1 purple tang, male and female percular clown's, 1 yellow wrasse