A dying question?

[shrimpchips]

Perhaps I read wrong, but one thing that struck me is that you said all the fish are dying/dead but the corals all remained fine?

I've had SPS corals survive out of a bag that reeked of death and were probably off the chart in ammonia - but fish would have been dead in that water for sure so maybe you had an ammonia burn or something similar due to stirring up crap, and also having a lower total volume (due to water displacement by the buckets of water). Maybe you had a dissolved oxygen issue also? I find that a lot of mysterious mass deaths in the night can usually be attributed to DO issues.

That being said, this is one of those "crashes" where the source is going to be difficult or impossible to pinpoint. But a better water change regimen would be a good place to start.

[shimmy]

The deaths did not happen during the water change so having the flow off I still don’t see the chance of that being what was the cause. I tested for ammonia as soon as I had noticed it and found nothing on my tester and same with the chlorine testing. Im thinking from everything people have suggested is that I had too many fish in my tank for the age of it and to be aquascaping and playing around in my tank shook the ecosystem too much.

[FitoPharmer]

just wondering, what is your turnover in your tank? how deep and what size of sand do you use? are you running a skimmer? do you know how long was it between you moving your rocks and the fish gasping? and what was your PH after the crash?

[shimmy]

Im running currently a fluval 304 (I have a larger pump just not fitted yet) and I have a powerhead that runs 1600L/H no sump.
The tank is a 72 gallon bow front (48”L 24”H 12”W) I have about 60 pounds of like rock and about 40 pounds of fine sand (cant recall for sure how big the bags were).
Currently not running a skimmer im still trying to find one.
I finished moving all the rock around 14:00 and found them in trouble around 22:00.
My PH has never moved its always been 7.8 - 7.9 (that was tested as well after the wreckage).

[FitoPharmer]

the 305 fluval, i guess the 304 is the older model, is 260GPH.
and the 1600 L/H power head is 400GPH.
660 for a 72 is less then 10X turnover very bad for accumulation in sand bed.
did you run your fluval with or without media?
and there wasn't any other circulation? 20X+ is best for reef tanks.

[shimmy]

Yes it is a fluval 304 its so OLD they have not made replacement parts for it in over 8 years at least im told.
But I have an Eheim Filter 2215 and trying to fit it onto my hard piped 304 setup. Yes I do run the pump with media so the flow is even less.
How could I get my flow up with out adding more powerheads for it sounds like im low on flow?
During the rock relocation the flow was off but was turned back on I completed my goal.

[shimmy]

Ok so something did not sound correct to me about the flow for my powerhead and there is, it is actually a 1600 G/H powerhead not 1600L/H.

[Ian]

First off very sorry to hear about the crash. I too am fairly new to this and the learning curve is harsh.
What others have said about the cycle taking much longer that expected is so true. My nano is so much easier to take care of now than it was 6 months ago. I have added/removed nothing in that time( except water) it just keeps getting more and more stable.
One thing nobody has talked about yet is surface agitation. By using a canister filter you have limited gas exchange in your fitration system so it increases the importance of having the surface of your tank turning over to get oxygen mixed throughout your entire water volume.If your pump and power head both are not causing ripples on the surface of your tank this could have made oxygen levels lower than expected and add another factor into this problem.Just an idea from one newb to another.
Good luck getting things going again

[shimmy]

Yes my powerhead generates lots of waves I even had to move it lower into my tank for I use to have a world pool that was sucking up air