One more question... does anyone have anyone with the ph tester drops??? well i tested my res and its yellow and it says that its 6.0 but it got me thinking... how do i know if it's not like 4 or something... does it turn to blue or something after it gets lower??? i tried an experiment one time putting a bunch of ph down in a tube that i was testing and i dont think it changed colors but stayed yellow but i was high so idk