Two fishy deaths. More to come? The culprit? Please HELP.

[verucaproduce]

I awoke this morning to find that two of my little platys had kicked the proverbial bucket.
A little background.

Ammonia=0
Nitrite=0
Nitrate=don't have test 'cause I am unemployed and cheap
Ph=7.8 - 8.0
Weekly water changes (usually on Sunday)
Tests twice a week
Thursday added a new heater. Titanium w/remote temp control.
Friday added Flourish excel organic carbon (for the first time ever)

I noticed late Thursday after I installed the new heater and rearranged the plants that the platys seemed to hide toward the bottom of the tank in the back. I thought this was due to the change in scenery and that I messed up their feng shui.

Friday seemed to be the same so I pulled some of the plants in the tank forward to give them a bit more 'privacy'.

Saturday seemed to be the same with them hiding toward the bottom back of the tank. Mr. Betta seemed ok except that he had no playmates. I should have done a water change at this point, but since I was going to do one today and my bf was over...I figured it could wait.

Sunday morning I find two little fishys laying at the bottom of the tank. Immediately did a 25% water change. Two of the remaining platys are toward the top middle of the tank but are not very active.The third is on the bottom of the tank. Fins look fine. What do you think could be the cause of their demise? High nitrate? Carbon? The temp has remained stable with the new heater, so I don't believe that is it. Please help with your opinions on what I should do.

10 gallon HOB filter with 1 Betta, red coral platies, real and artificial plants.
5 gallon UGF with 3 otos who are anxiously awaiting their new home.

 

[TankGirl]

You may have stirred up some gunk in the gravel when you moved the plants, and I would suspect a nitrate jump as debris entered the water column. It may not be at a terribly toxic level, but it is the sudden change that was difficult for the fish. I would do a water change, just like you did, maybe every other day and hopefully get this back down. Sounds like you are handling it in exactly the right way

Assuming you used the proper dose for the Flourish I would not suspect that as responsible, though you would need only maybe half a cap-ful for that tank.

 

[verucaproduce]

I used a whole capful of Flourish as per the dosing instructions on the back of the bottle. I hope that didn't set this whole fiasco in motion.

I wish I had known that nitrates could prove fatal, as the vast majority of people in another forum seem to 'poo-poo' them. I was under the impression that they wouldn't have a big effect on the fishes' health, which is why I didn't invest in a test a lot sooner. Live and learn I guess.

I am going to try to get a nitrate test in the morning. I have a bad feeling that there may be another demise while I am sleeping. But I fear that moving fish around may only make things worse in the end.

Wish me luck. :?

 

[TankGirl]

Higher levels of nitrate is not in and of itself a killer - many fish can tolerate amazingly high ppm - it is the shock of suddenly going from low levels to higher levels that does it.

I had a very similar thing happen to me when I was overly vigorous with a gravel vac once in a small tank - nitrate spike occurred and I stressed the fish, but a couple of quick water changes and we were back to normal.

As is the case with many of the water parameters we monitor, like temp and pH, to name a couple, it is not necessarily bad as long as it is stable - you make a sudden change and the fish have trouble.

I do wish you luck - and you are absolutely right that moving the fish is another stressor, and I will say again that you are really handling this in just the right way. From the info you have provided, a nitrate spike is all I can blame, so the jury is not out, but partial water changes are always a good idea when something unexpected happens.

 

[verucaproduce]

TG,
Thanks so much for your explanation. It really makes sense now. We made it through the night without another casualty which is a good thing.
So I am guessing that it would be a good idea to do a nitrate test after stirring up gravel etc, especially when not doing a water change? Or when your fish are acting 'suspicious'. Funny part is that I did all the tests I have in the house trying to figure out what was wrong. I should have listened to my instincts earlier and done a water change. *sigh*
Well, if I make it through this I will be sure to pass the word on to all my fish friends.
Someday I will get the hang of this. Really I will.

 

[TankGirl]

Someday I will get the hang of this.

No doubt about it!