
Yes, I have that knotted gut feeling. Also because I haven't eaten breakfast yet....my next task.
Here's the damage..........
It appears to be a combination of circumstances that did the damage. I'm suspecting that one or two Tiger Barbs died. They've been popping off one or two at a time for a few weeks now. Old age I guess.
The Aquaclear 500 HOB intake sucked up a load of plant debris from the copious growth of Windelov fern in the tank and knocked its flow way down. Normally, this causes a lot of surface disturbance, so I guess O2 levels dropped.
And then, one of the Rena's had suddenly slowed up. It too had oodles of plant debris in it and it returns via a spraybar mounted crossways near the top of the tank. Again this causes surface rippling and that was reduced too.....more O2 depletion.
Remedial action? Cleaned out the HOB intake, cleaned the Rena.....it was only done two weeks ago......I rotate doing each Rena (there's 2). I also put a positive air feed onto one of the small powerheads on the River-Tank manifold in there so now there's positive air bubbling going on.
Lessons to be learned? Big fish need lots of oxygen. When you've a lot of Clowns in a tank have multiple systems for filtration and aeration. If one fails, there's backup. I was real unfortunate in this case that the two primary systems that cause surface agitation failed at the same time.
Momfish lost a bunch of
Uaru years ago when a filter hose collapsed. Same effect, low O2 levels.
In this case the dead Tiger Barbs probably was the clincher. I haven't checked Ammonia or Nitrite levels yet and no doubt they're reduced by the 60% water-change, but I'm betting they were not good because the water smelt fishy.
Right....I'd better go eat some breakfast....not that handling slimey dead smelly fish first thing in the morning is good for the appetite.
Sh*t!
Martin.