I left the chemical run through the filter. I have no carbon in my media, think i did it on a Wednesday and my 20% W/C's happen on a sunday, so 4 days I let it cycle around. Even though the hydras were instantly killed within 24 hours. So it definitely seems shrimp approved (even though amano's are more hardy than others).
I would suggest dosing the tank - leaving the filter off for 30 minutes, turning it back on and then waiting 24 hours before doing a W/C of 50% if you want to be on the safe side. If you have a carbon filter, you can also use that as well to purify the water again.
I kind-of wish i got documentation with photos but my camera is crap and I used a few products before safe-guard that LPS said they would work and didnt come close. I probably had about 200+ hydras in my little 6 gallon by the time I found out about safe-guard method.
Last edited by Vermino; 06-20-2013 at 01:23 AM.
Reason: added a bit more information