Algae Scrubber Disaster

[Myka]

Originally Posted by monocus

my scrubber is built the same way sitting on my sump with 2" clearance to the top of my stand.i've never had any problem while or after changing.it almost sounds like your o2 is very low in your tank and when you turn the pumps off the o2 is rapidly depleted.you shouldn't be getting a spike in ammonia by changing your algae scrubber which soaks up nitrates and phosphates

Exactly what I was thinking, it does sound like oxygen deprivation. Ammonia won't spike that fast. I'm not really confident that oxygen would deplete so badly in only 5 minutes though. I have a hard time believing your tank is so overstocked that one of several pumps being off causes almost immediate oxygen deprivation.

Do you have a skimmer on this tank? Are the return pump and powerheads still operating while you clean the ATS?