Re: what is the ph of your tap water? The reason people use ro/di is to remove disolved solids; phosphates,copper, lead, silicates, iron, and other nasty things.
Not so much to change the ph.
Without ro/di you are opening yourself to a heap of trouble, algea and cyno outbreaks, Potentialy copper could enter your system. Copper would prevent you from Keeping inverts and coral.
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100 gal touch tank for propagation;Current Sunpod2 HQI @1400k HQI ,38 gal Korrall sump, ASM G-3 skimmer, Mag 9.5. Stock changes often 125 gal ;Aqualight Pro HQI 2 HQI@1400k / Compact Fluorescent/Lunar Light Fixture, 5 powerheads, 30 gal sump, mag 12(return),Ocean runner 3500(return through chiller), ASM G-3 skimmer, UV sterilizer, Artic chiller Tobacco bass, maroon clowns, Seriatopora guttatus, Seriatopora hystrix, capricornis, Acropora, Spongodes, porites, Turbinaria,Stylophora pistillata, etc |