I have my 260g with direct co2 injection in my enclosed office which is only about 12x18 with no ventilation; my eyes are burning today; has anyone had any trouble being in close proximity to their tanks on extended periods (8-10hrs) with co2? Thanks for your help, Jeff A. _______________________________________________ GSAS-Member mailing list GSAS-Member@thekrib.com http://lists.thekrib.com/mailman/listinfo/gsas-member