Added flow and also introduced the proper dose (for a 30 gal tank) to my aquarium of the eXit after siphoning out as much of them as I could (not too many out and about). After about 45 min I added the proper 1/2 dose as per instructions. Its been about 1 hour total and 15 min since the 2nd dose and none of them seem to be dropping dead. What should I do next? Looking for any more advice...more eXit? thanks!