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Fish rapidly dying

3K views 22 replies 3 participants last post by  PhatRam32 
#1 ·
Ever since I changed filters from a tetra whisper filter to my aquaclear filter, I have had 4 fish die in the last month and a half. Not sure if this is a coincidence or not.

I tested my water and all levels seem to be within normal range except for the carbonate hardness. All of a sudden it is through the roof at 240 mg/L. I perform water changes every 2 weeks and never had a problem until lately.

I have had a swordtail, female betta, 2 gouramis due recently. My other fish (zebra loach, dojo loach, pleco, pictus catfish, paradise gourami, powder blue gourami, and silver gar) are doing just fine, luckily.

Any suggestion and advice would be greatly appreciated.
 
#2 ·
Did you put the media from the tetra filter into the new aquaclear? If you didn't you could of easily sent your tank into a mini cycle. Can you post water stats with numbers, regardless if its okay or not. Also what test kit are you using.

BTW you have some very incompatible fish sharing that tank, which could be the reason for the fish loss. If it isn't now it will be down the road when they start eating each other.
 
#3 ·
I did not put the media (you mean filter?) from the tetra filter into the new aquaclear. I just did a straight up change of filtration systems. The test kit I am using is the 5 in 1 test strips from API. Yes it is an odd combination of fish but they actually get along just fine.

Water Stats

GH 60 ppm
KH 240 ppm
PH 7.0-7.2
Nitrite 1 ppm (lower end of spectrum)
Nitrate 40 ppm (lower end of spectrum
 
#5 · (Edited)
yeah you lost your cycle when you swapped filters. If you are unfamiliar with cycling an aquarium I highly suggest you research the topic. Bacteria is in the filter media that breaks down toxins produced by the fish. This bacteria take time to establish, 4-6+ weeks often. Without it the toxins build up in the water and kill the fish. Not saving the media from the tetra filter caused a large loss of bacteria resulting in fish loss. Your nitrite at 1ppm is high, easily high enough to kill gouramis. It should always be zero, since it is toxic to fish. The presence of nitrite almost always happens alongside an ammonia spike, which again is toxic and can easily kill your fish. The ammonia spike comes first since it is produced by the fish with the nitrite following. Your test strips do not test for ammonia. I would recommend getting an API liquid test kit its what many people use.

Currently I would recommend a large water change. 50% at least to cut down the nitrite levels. You will be doing a lot of water changes for a while to keep levels down until the new filter establishes. 50% every other day if not more. A better test kit will help you determine this. Stop feeding the fish for the most part, like once every 3 days or so to try to slow down the build up. For the future always transfer media when changing filters. Even if you need to shred up the old media and shove it in the new filter it will avoid water quality issues. Its usually recommend no more then 1/3 of the filter media be replaced at one time.

The tankmates may be fine for now but 4 gouramis in one tank was asking for trouble. The pitcus and gar will potentially reach 8-10" in a proper sized tank. Just don't be surprised if smaller tank mates disappear one night.
 
#6 ·
Thanks for the info. My tank was due for a water change tomorrow anyway and maybe that's why my nitrite levels were a little high? I have had the new filter for 6 weeks I guess the cycle is not quite complete. Is this also the cause for my carbonate hardness to increase? It seems my bottom fish and my gar are quickly more adaptable than my other fish..hmm
 
#7 ·
Nitrite should be zero no matter how long between water changes. Far as KH I would bet that is something to do with your water utility or possibly the test strips misreading if they were stored improperly. Its unlikely IMO that a change in KH killed your fish, nitrite and ammonia are much much more likely causes. Only other cause for KH if it measures higher then your tap water is the presence of crushed coral or limestone in the tank.
 
#8 ·
Thanks again. I just bought another biomax media and will be taking out my carbon and running two biomax medias along with the aquaclear sponge. I heard that should at least help more with the nitrite problem. In the meantime water changes it is until the cycle is complete.
 
#10 ·
I heard that should at least help more with the nitrite problem. In the meantime water changes it is until the cycle is complete.
Even if it worked as advertized, the biomax will not help with an existing nitrite issue fast enough to be of any immediate benefit. The idea is that it will house oxidizing organisms that do oxidize nitrites in the medium term assisting in the overall nitrogen cycle capacity. Your tank will rebalance with or without the added biomax.

Jeff.
 
#9 ·
How large is your tank and are there any live plants?

The nitrite reading indicates that you have messed with the cycle capacity and this should be, as noted, zero. Replacing the filter does not remove all of the bio-film (ammonia and nitrite oxidizers), depending on the tank/filter it may not even remove half of them but that will still upset the balance.

I'll assume that you are using city water supply and your are treating the water with some sort of conditioner... if it's Prime, then the nitrite will be rendered non-toxic for a day or two. I'd suggest not only doing the 50% change, but change some every day or two treating it again until the nitrite subsides... you don't mention ammonia, it will probably be high as well but Prime handles this... some conditioners don't do everything.

I was going to suggest not wasting your money on more biomax as it appeared, at first glance, to be the typical ceramic material as others that are just too fine porosity to be of use in the aquarium setting. So before I put foot in mouth I thought I would check it first.

I have biomax in the office aquarium filter so I pulled one cylinder out, it's not hollow like some are, and broke it apart to see if there were any signs of water flow through. There are. Here is a shot of the broken cylinder and the obvious larger granular look to the inside with the discolouration of particulate buildup. Other ceramic materials show no sign of water inside the material like this.

Even so, I wonder how long it is good for as the particulate builds up inside the cylinders it must block water flow the same as a fine sponge would as it's pores fill with material. In the case of a loose group of cylinders you would never really know as the water will just pass around them anyway and the flow through is going to be minimal, even initially.

I guess I still side on the "don't waste your money" side of the argument. If I recall, this stuff is around $10 for a small pouch whereas huge amounts of polyester floss can be had for that price and be as good a bio-film support medium.

Jeff.
 

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#11 ·
Thanks JDM My tank is a 15 gallon tank. Will be doing a 50 percent water change today and smaller water changes on a daily basis until I get the nitrite level down to 0. Yes, I am Prime so it does include eliminating ammonia. I just had another fish die on me so down to 6 =/. I wish I had done the filter swap the right way from the begining.. but oh well nothing I can do about it now except for this. How long do you think it will take to get the nitrite down to 0?
 
#12 ·
It could be a couple of days... but it could be longer. I had this happen due to adding too many fish at once and it lasted two to three days.

If you start testing for ammonia, keep in mind that it will appear after using Prime, though it is non-toxic at that point and that ammonia is still available to oxidize into nitrite... Prime doesn't actually remove the ammonia that it created while breaking down the chloramine.

Jeff.
 
#14 ·
Sad to say another fish died.. my paradise gourami. I am down to 5 fish now. The remaining live fish I have had between 3 months to 2 years and with my old tetra whisper filter before I made the switch. However, the fish that I did add after I made the filter switch to aquaclear, all of them died which i guess now that I read this is not surprising since I threw my tank into another cycle. As for the test kit, is this a good one to use vs the test strips? Amazon.com: API Freshwater Master Test Kit: Pet Supplies
 
#15 ·
Yes, that is a very good test kit.

Sad to hear that you are still losing fish. Depending on a lot of things they could just be succumbing to damage already done and there is nothing that you can really do for that other than to keep treating and changing the water so it is as good as you can provide.

Jeff.
 
#18 ·
I had pet supermarket test out my water.. figure why not since I was there getting my reptiles food. Not surprisingly.. everything checked out ok.. Ammonia levels were at 0 along with nitrites.. The fact i did 50-60% water change probably is the reason why but will wait a few days and test the water out and see how it is then. I may have lucked out or at the tail end of the cycle. Hopefully this continues to hold :) Some encouraging news at least.
 
#19 ·
It is Friday and tested the water out again because I am crazy like that lol.. 0 Nitrite and 0 Ammonia. The remaining 6 fish are doing just fine as far as behavior and what not: silver gar, white skirt tetra, zebra loach, bushelnose pleco, dojo loach, and pictus catfish. Odd mix yes but they actually get along quite well and have been for some time.
 
#20 ·
Tested the Water today for ammonia using the API liquid drop test as before and it is some where between 0 and 0.25 ppm.. Based on the color it is more on the yellow spectrum and if I had to estimate id say 0-10 ppm. This tells me a water change is needed today.. How much of the water should I change though after I did a 50% water change last Wed?
 
#21 ·
0-10ppm.... I assume this is the nitrate reading? A good goal is to aim for 10ppm as the maximum as the lower the better for the fish. I aim for 5ppm b it it is very easy for me as my tank does not create enough nitrates to worry about, I've never measured over 5 yet and I have skipped a few WCs ,along the way.

Maybe just set your schedule changes and start now... 25% at least. I always think that once you get the change going, 25% or 50% is just a matter of a few more minutes draining or filling so why not go for 50% all the time?

Jeff.
 
#23 ·
Happy to report that I have 0 Nitrite and 0 Ammonia in my tank =D. Nitrate levels are withing appropriate levels and with my routine water changes should not be a problem.

No fish deaths as of 2 weeks when Sh*t started to hit the fan. Will be buying a few new fish soon and see how they do.
 
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