Panaque collection mysteriously dying off

[oppleco]

Im puzzled my royal collection of four has been mysteriously dying off this week. Only fish in tank affected . Lost my third one in three days only full spot L330 left. Any ideas? thank goodness I placed my Thunder pleco in another tank


1. Water parameters
a) Temperature range. 81 F
b) pH. 6.5
c) GH. ?
d) KH ?
e)Ammonia, Nitrate, Nitrite, levels. Nitrate 40 PPM its always 40 PPM
f) Water change frequency 1X week 100 gals
(Most LFS's will check your water and give a list of readings).

2. Tank set up
a) Size. 360 system - 240 tank and 120 gal sump
b) Substrate. slate
c) Filtration. Sump and 2260
d) Furnishings. driftwood
e) Other tank mates. cichla and Red hooks
f) How long has it been set-up? over a year
g) When was the last new fish added? 4 months ago - 2 royals
h) Foods used and frequency?, fed every other day , massivore, colbalt algae wafer , hikari mini wafer

3. Symptoms / Problem description ,, no symptoms, no marks, no sunken belly or eyes , normally they are in the bogwood . I noticed the first one two days ago , he floated to top.. did water change added , Seachem safe. next morning a pleco was in front in the open. noticed he wasnt moving but looked healthy ,, dead! pulled him out did another water change .. next evening a third pleco looked like he was grazing on rock.. also dead. no clue the papa pleco Ive had for 4 years was first , followed by my new 8" broken line, today L191 (2+ years) .. no clues new L330 only one left.

4. Action taken (if any) water changes , increased water aeration

5. Medications used (if any) none

[amiidae]

Google "Panaque plague" and see if it matches.

[oppleco]

i noticed no lesions , let me take pleco out of freezer and re-examine

[PseudaSmart]

Getting to the root of the problem requires careful attention to detail. I have spent a year understanding my problem with Pseuda fry deaths. What delayed the process was making too many assumptions. One example was assuming that a manufacturer never changed their formula. It was not until I actually ran tests did I find a change!

I did see that there are other fish in the tank. In a large tank the composition of the water during a WC will be very different throughout the tank until it mixes. Some fish are hardier than others.

Reading your post reminds me of recent events

Do you use city water? Several times a year some cities crank up the chlorine compounds. A friend lost a tank with plecos in less than an hour. It took 4x the normal amount of prime to remove it. They died in place. One place I lived you would turn on the faucet and the smell would hit you. I didn't even try to do WC's until the smell was gone.

It sounds like you add the Seachem safe directly to the tank after the water change?
As you are filling the tank the fish will be exposed to the untreated new water.
Adding to the tank creates a chemical reaction in your tank which will stress the fish.
Until everything is properly mixed your fish are at risk.
If a holding tank is not possible at least add the safe to the sump and then add the water to the sump.

Another possibility is ph bounce. You need to check GH and KH. I know it can be confusing but it is the way to check. What is the ph of your water supply? I know your first reaction is that you checked the ph and it did not change. Did you check it right after the WC?

Last bit of advice. Always look at the effect of any action you take.
You found one dead(looked healthy). Did a WC, a good choice. But....
Found 2nd dead(looked healthy). Did another WC. But...
Found 3rd dead(looked healthy).
One moved to other tank is fine.
One logical conclusion is something is wrong with the new water.

I hope you find the cause.
Jim

[apistomaster]

I can't explain why your Panaque have been dying.
My comment has to do with chlorine/chloramine neutralization.
I have always used about 3X more SeaChem Prime than is indicated on the label. I am generous with it precisely because without an accurate test, I can't know what the exact levels of chlorine compounds are in my water at any given time. For years I never used any dechlorinators without any incident. But one time I changed the water in most of my tanks and many different species died. After that incident I vowed, never again. I typically changed about 70% of the water every 3rd or 4th day.
I added all the Prime prior to refilling my tanks directly from the tap and it has never affected the most sensitive species I've ever kept.