Just lost a tetra...after 50% pwc

[Taelen]

I just did my usual weekly PWC to 50% and I'm not sure what has happened but all the fish appear to be distressed somehow (whether it's swimming strangely or in odd directions or what I think is called "flashing" when they swipe the gravel) and I just lost one of my black phantom tetras.

Hopefully someone can let me know what's happened and what I can do before something else happens.

I tested the parameters twice in the last hour and there seems to have been an ammonia spike somewhere around 0.25ppm, although I'm not sure how as I didn't really do anything different. I vacuumed the gravel as I always do...did I release some kind of gas pocket? Nitrate and nitrite were fine while pH was a little higher than normal, around 7.2-7.3.

Another thing I did today was change the filter in my HOB. When I do this, there seems to be a bit of debris that floats in, but this has never caused the fish to react this way. Should I do another PWC right away or should I wait. Not sure how to proceed at this point.

Any help would be appreciated.

 

[Lonewolfblue]

Could be from gravel vac and changing the filter, causing a small mini-cycle. If things go back to normal, you should be fine. Keep us updated.

 

[Taelen]

With the exception of my pearl gourami, all of the fish seem to be down near the bottom. Should I wait a couple of hours and test the parameters again? Or in other words, how soon should "things go back to normal"?

If the levels don't return to 0, when should I do another PWC? Which I assume would be the way to go, but strange that I just did one..?

 

[Lonewolfblue]

Just keep an eye on ammonia and nitrite levels. If they get above 1ppm, or preferably above .5ppm, do a PWC. Usually in a cycled tank, if you have a mini cycle due to doing too much, it could last a day or 2, but should go back to normal, as the bacteria should recover fairly quickly.

Also, use liquid test kits and not dip sticks. Dip sticks are usually inaccurate, from my own experience with them.

 

[Taelen]

Yep, I use the API Master Kit, so no worries there. I took the readings twice just to be sure.

I'm just very paranoid (especially after losing a seemingly healthy fish so suddenly) that I have done something very wrong and I'm going to lose everyone.

I'll do another full check of the parameters in a bit and post what I find.

Thanks a lot LWB.

 

[Lonewolfblue]

Not a problem. And if the fish are still acting a little strange, doing another 30% PWC with no gravel vac should help them. Also, do you use Prime for dechlor? If you do, then I would recommend doing a double dose.

 

[Taelen]

I don't use Prime specifically, but I do use a dechlor. I was always worried about maybe adding too much dechlor, but if they are still a bit off later tonight, I'll do a slightly smaller PWC.

 

[Lonewolfblue]

As for the dechlor, only do the recommended amount. Prime is the only one where they recommend additional dosing to counter the effects of nitrite. So if you don't have Prime, don't double dose. Even though I don't think it will hurt the fish, I wouldn't do it. Just do the PWC's as necessary. Keep levels below .5ppm. The mini-cycle should pass quickly.

 

[Taelen]

Update for this morning.

I've lost my rainbow shark and there still seems to be one of the black phantoms who's having trouble. I've just tested the parameters again, ammonia still seems to be somewhere between 0.15-0.25. Nitrate is now up to about 5ppm or so. All other parameters are fine. I have to rush off to work this morning, but I will do a 30% PWC when I get home this evening.

I guess next time I should maybe replace the filter, then do a PWC shortly after? I can't think of any other reason why this would have happened. It's a little distressing.

 

[rich311k]

I don't think it had anything to do with the slight ammonia spike. It is certainly not that high.

Was the temperature of the new water close to the tank temperature?
Did you check your tank and tap KH?
Maybe the water company changed the water somehow? Are you 100% certain you added dechlor to the change water?
Did you do anything different than you usually do? Add anything new?

 

[Taelen]

What I usually do is while the new water is being added with my python, I add the dechlor into the stream.

As far as the temperature goes, I try and get it as close as possible, the first little bit of water I add back is at a very slow rate. I check the tap and then check what's coming out of the python compared to the existing water temperature. I have never actually used a thermometer to do this..maybe I should?

KH is the one parameter that I have never really kept an eye on, I will buy the API KH test on my way home today. I didn't think our water was that hard. I put some grass seed down this weekend and have been watering my lawn pretty heavily, but I can't imagine there would be any link.

Other than that, I can't think of anything different. Hopefully, the city hasn't done anything to the water.

I thought that the "panting" and "flashing" behaviour were indicators of the elevated ammonia, but would temperature or hardness also cause them to do these things?

 

[rich311k]

I am just wondering because your ammonia levels never got that high. Tetras are pretty tough. I think that a slightly elevated ammonia level would not kill fish that quickly. The gasping and flashing is a sure sign the fish are under stress, could be a lot of things. In any case I do recommend another water change. I would check the tank and tap KH first.

 

[Taelen]

Thanks for the help guys.

I will check the KH , then do a 30% PWC as soon as I get home. Hopefully everyone is still ok. =(

 

[Lonewolfblue]

Let's hope that all are still ok. As for the gasping and flashing, it does seem like maybe the ammonia level could be higher than what the kit is telling you. If it's not too much out of the way, might take a water sample to the lfs to have it tested, just as a double check. Once this passes, the next time I would do the PWC and gravel vac first, then a couple days later, change the filter pad if it's necessary. Several of us rinse ours out several times in tank water and re-use til it is in bad shape. Just another idea to look at. Let us know how things are when you get back home.

 

[Taelen]

Well no more fatalities thankfully, although everyone still seems to be stressed. The remaining black phantoms have lost a bit of colour.

I tested the KH as suggested and it took 2 drops to reach the endpoint, so from what I can determine, that's approximately 35ppm? Please correct me if I'm wrong.

I also did a 30% PWC. Upon closer inspection of my dechlor product, I realized that I may have not been adding enough dechlor to my tap water. I feel awful about it, I may have inadvertantly been poisoning the little guys the whole time. I made very sure to add the correct amount tonight, so I will re-test all parameters in the morning to verify. I will also take some water to get tested at the LFS, to be sure there's nothing goofy going on with my API kit.

As for the advice on the filter, this sounds like a much better idea, re-using the old one, the one I replaced wasn't too bad, I just changed it based on the period of time that had passed. And I will also make sure to do the tasks a couple of days apart as well.

Thanks again, and I will post an update tomorrow.

 

[rich311k]

Hope the night goes well. Looking forward to good news in the morning.

 

[neilanh]

My bet is on the water more than the dechlor issue. Thats a very low kH, and can attest to pH swings. I'd keep up like you plan on doing, but check your kH again in a week or so and see if it's the same. Something may have happened to shift it, and that can cause fish to stress.

I do my PWC process the same as you with regards to filling and adding the dechlor into the stream. Make sure when you're doing this you dechlor enough for the whole tank, not just what you estimate as how much you're putting in.

My fish always hang out at the bottom during the PWC process and for a bit afterwards. Never seen any flashing, but they do hang low in the tank for a few hours.

 

[Lonewolfblue]

My fish are just the opposite. They love swimming in the stream of new water coming out of the Python. And some of the tiger barbs try to swim up the python when filling. Even my sharks tend to be attracted to the fresh new water, and the loaches love it too. But mostly the tiger barbs.

As for the dechlor, I just dose mine to the total tank size, and just dump it in the general location of where I'm filling, and let the circulation of the new water spread it around. Never had any issues doing it, and I tend to do 50%+ per week PWC's.

 

[Taelen]

Well, everything seems much better this morning. Tetras have their colour and they seem to be swimming around more now. Didn't get a chance to test the parameters this morning, but I will do so after work once again.

I am seeing something that I was doing incorrectly for sure, I have always tried to estimate the amount of new water going into the tank for dechlor purposes, I see that you guys are dosing for the whole tank every PWC. Is it not possible to put "too much" dechlor in?

The type of dechlor I have removes chlorine, chloramines and has some kind of stress coat product in it as well. I didn't actually buy this stuff, it was left by the original owner of the house as this is an inherited tank.

 

[LandGhoti]

Yes, that's what I do, too: dose the whole tank when I do a PWC (50% once a week), not just for how much I'm refilling. After 24 hrs, the chemicals have all diffused so it's OK to dose for the whole tank once a week (if that makes sense).

What kind of dechlor do you have?