RDA section on sub tank. Built a 0.7 ohm coil checked with ohm reader. ipv mini 70 watt fires it at 0.7 Sigelei 30 watt fires it at .07. ipv mini 30 watt reads low resistance but fires another tank at 0.5 ohms Hana Modz 30 watt low resistance reads low resistance but fires another tank at 0.5 ohms also. Does anyone knows why the other 2 wont fire it