Fish die-off after water change/plant moves - anyone ever had this?

[jbrady33]

So I did a WC on my 36 gallon tank (in sig). About 40% with a water changer - I'm on well water. Before change I was 0/0/20 with no ammonia, after it was 0/0/10 and no ammonia (and no chlorine). Temp of the tank only change by a degree or 2 (78 to 76 or so)

I moved some plants around (some stuff got tall in the front), and trimmed/removed some ratty leaves. Took about 40 minutes total with the filter off.

Immediate loss of the 6 Cardinals I had in there and about 5 chili rasboras. 6 Platy in the tank are hiding, but moveing and fins not clamps. Ottos being thier normal self, Amano shrimp are fine, RCS look ok, Pygy cories hiding to well to tell.

The dead fish seemed to drift in the current like they were in a coma, coming to once in a while and finally having no reponse at all. No sign of disease, they were 100% normal before I started.

What gives? You ever have this before?

[wkndracer]

suggest setting a glass of well water on the counter overnight.
pH test it right out of the tap and do another one the next day.
large shifts in the reading would tell you the well water was O2 deficient or loaded with CO2. (just guessing)

sorry for your losses.

[mistergreen]

When you disturb the substrate, changes are ammonia will escape the substrate and into the water column.

[JSE]

Originally Posted by mistergreen

When you disturb the substrate, changes are ammonia will escape the substrate and into the water column.

Aren't shrimp much more sensitive to ammonia? He said the shrimp were fine.

[wendyjo]

Originally Posted by mistergreen

When you disturb the substrate, changes are ammonia will escape the substrate and into the water column.

This isn't all that common tho, is it? I hear it blamed for alot of bad things, but I've never had any fish loss after tearing/moving plants for rescaping even tho it typically makes a pretty big mess.

[jbrady33]

I think wkndracer my have figured it out:

Glass of water right out of my tap (with the aerator unscrewed, just like it would be with the water changer) gives:

6.2 or lower PH (low as the test will read)
0/0/10
0 GH
no chlorine

After 12 hours standing on the counter, ph reads 6.8.

Not fond of airstones in the tank all the time, but looks like I need to run one during water changes (and to let it splash in from above the line, not gently enter underwater)

[jbrady33]

I think the carnage is over, Platies are acting normal again, a handful of Chili Rasboras made it, 2 Amanos still kicking, saw at least one pygmy cory. Haven't seen an RCS since the day it all happened though

This loss was extra hard, as I purposely went low tech as I never wanted to have Co2 equipment fail and gas the tank.