Possible contamination

[naitch1980]

I have a possible contamination in my tank.

The reason I believe the water is slightly contaminated is because I lost a 3 year old black tetra randomly and the other fish appeared to have breathing difficulties. My tank is only 2 weeks old, but we'd been given an Angel fish, 2 black tetras and a cooly eel by my girlfriends father, as he is unable to look after his tank now. 5 days later, one of the tetras die.
I don't think it's due to ammonia levels being high, as i've treated the water for ammonia anyway.

Now, I was told the way to deal with this was to do a 50% water change, followed by 30% every day for a week (as long as the fish were still having difficulty).

So I water changed - 50% on day 1 after the fish had died.
Day two I did a 30%. Then I popped to Pets at Home to pick up some plants (I never buy fish from there) and my girlfriend mentions the situation to te "expert" there who says I have done wrong and i'm putting my fish at risk, i should have taken a water sample in for a free check.

Now, while I'll go ahead with the free check, I'd like to know the opinions of other people on how they would deal with potentially contaminated water in the meantime. The reason I don't want to empty it all out & start again is because I want to get my Eco-system up and running.

 

[dskidmore]

Well, if you have your own Ammonia, nitrite and nitrate test kits, then you can probably do better than the free check at the LFS. (My LFS isn't too careful about the way they perform those tests, I don't trust the numbers.) If you don't have your own kits, definitely go for the free check, or better, buy your own kits. The LFS likely does not include cleaning agents other than ammonia in the free check, so if this is really a contamination case, they won't catch it.

Could you post your ammonia, nitrite and nitrate levels? It sounds like your tank is awfully heavily stocked for a 2 week old tank, you might have nitrite poisoning going on if your ammonia is 0.

Water changes are a good thing when cycling a tank with fish. During the heat of the cycle, 50% twice a day is reasonable. Get your own test kits to find out how often you need to change the water. You could also use a product like Prime to detoxify the ammonia an nitrite in the tank between water changes.

If this really is contamination, I'd do several major water changes, and put as much activated carbon in my filter as will fit. Change the carbon daily until you think the water is clean. If this is ammonia or nitrite poisoning, daily carbon changes will be counterproductive, as the carbon is another surface for beneficial bacteria to grow, and you'd be removing the bacteria with the old carbon.

 

[dskidmore]

P.S. If you take all the fish out, you do not have to start from scratch on your eco-system. Just continue adding fish food, and the micro-organisims will develop and grow into a colony able to support your prefered fish.

 

[QTOFFER]

Welcome to AA, naitch1980!

First, no cleaning sprays of any kind near the tank! Wiping the glass with a slightly moistened towel is much safer. If you suspect contamination, the best you can do is a big water change, add some carbon to the filter, and pray.

Second, how big is the tank?

Third, if it's only been set up for two weeks, it's probably not cycled yet. What are your ammonia levels, and what exactly are you doing to treat it? (Ammonia treatments convert ammonia to a less toxic form, but don't eliminate it - they also slow down the cycling process.) During the cycling process, you need to test your water every day - especially if you're cycling with fish- and do a PWC when the ammonia or nitrite reaches 0.25 ppm.

Finally, how do the new additions look? Any signs of ich? Ich starts in the gills and can quickly kill an already stressed fish.

Your fish may have died from aggression by the angelfish, from an ammonia spike caused by the added bioload, or from a disease introduced by the new fish. Hopefully we can help you figure out the problem.

 

[SCFatz]

First off i'll agree that water changes are the only solution right now regardless if it is over spray or nitrites.
Be sure to temp match and declorinate before adding new water.

I'll second the notion that you need your own test kit.....especially if you plan on keeping the fish in there through the cycle.Buy a liquid one and not the strips.Te AP freshwater master kit is popular among users here and I use it as well...usually about 25-30 bucks in the stores,but worth every penny.In your current situation I would consider it a must have item imo.

You,ve set your self up with a challange but it will work out.You have found a great place on the web for help.One of the best sites out there imo.

 

[naitch1980]

Hi everyone.
Thanks for all the advice first off.
I stand corrected, my tank is actually 4 weeks old according to my girlfriend (doesn't time fly when you're becoming obsessed).
I have Ammonia, Nitrate, Nitrite & pH testing kits. I'm at work at present and don't have the numbers with me at present, except I know for a fact my pH is 7.6, because it started out at 7.8, so I bought some pH down and it dropped by .2 in a couple of days.
To be honest, when I got home yesterday, the breathing was still a little eratic, but I decided to leave it until this morning and it's settled down a lot. One thing I have noticed though is that the Angel IS chasing the other black tetra. I was adamant when we received the fish that the Angel would be aggressive, but it was insisted otherwise. He's a decent size too, about 6 inches(15cm) from tip to tip. The tetra is about 2inches long and now hides behind the filter all the while, only rarely popping out.
The tank incidentally is a 125 litre tank (i think that's 35 US gallons).

The fish look ok, but they have a more rapid gill movement -as if they're struggling to breath - than I am happy with. I have dechlorinated the water also - although, I could do with a chlorine testing kit, which I can not find anywhere.
I know the issue isn't about oxygenation of the water, i have several live plants in, and also an air bubble system.
I knew i should have set up an external filter straight away.

 

[coldmachineUK]

Judging from the breathing difficulties I think I'd have to agree with dskidmore that it's sounding like nitrIte poisoning, but without numbers none of us can be sure
You've already added oxygen, so that's a good thing.

Yep, I've never heard of angels and tetras mixing and becoming best of chums, but there's bound to be someone out there who has managed it! Next time you're at the LFS, you might want to 'mention in passing' that your fears were well founded... Sometimes staff are there to give a pitch, not help the customer sadly.

About the pH: the difference between 7.8 and 7.6 is minute, so I wouldn't have really bothered changing it tbh. Also, if you do ever want to alter the levels of pH in your tank for some reason you are best doing it gradually and naturally (say add limestone for an increase and wood for a decrease etc). This way it's less of a shock to fish. Most species can take less than ideal living conditions provided they're consistent

 

[dskidmore]

I agree with coldmachineUK. In a freshwater tank, let the fish acclimate to your local pH rather than messing with powders and liquids to change it. Stability is more important than a target number. With weekly water changes, your tank will stabilize at parameters near your tap water. If you're really concerned about local water quality, use half tap water and half RO/DI filtered water.

My angel did ok with the tetras she grew up with, but ate any new addition to the tank. (I wouldn't have tried the combo myself, but someone gave me her fish when she couldn't take care of them any more.) I eventually traded the angel in for some otocats.

 

[QTOFFER]

There's really no need to use pH adjusting chemicals. Fish are remarkably tolerant of a wide range of pH. It's rapid pH swings that they can't take - and those pH chemicals are prone to causing them.

Angels will try to eat any small fish that can fit in its mouth. Their natural prey is neon tetras. I keep angels with many large tetras and haven't noticed any problems. However, like all cichlids, each angel has a distinct personality, and yours may be the exception. If you provide lots of hiding spots (your plants are great), most tetras will be able to seek shelter.

 

[naitch1980]

Right, after continuous testing, it appears my nitrites are quite high. I'd say this is because I have too many fish in and my bacteria ecosystem isn't yet up to speed.
Any ideas on how I can reduce the nitrites using?
If anyone knows of anything availabe in the UK, that'd be great.
I was told to try Nitra-zorb, which I have bought, and used and it was sh*t, just did NOT work.
I was due my partial water change on the weekend, so I took 30% out instead of 20%, it's settled the fish right down, but the nitrites are already back at about 0.25 and are probably rising.

Any help would be great.

 

[dskidmore]

Your first defense is water changes. Change out as much water as you need to keep the nitrites below 0.5 ppm. Up to 2 75% changes daily.

Second defense: Salt can reduce the detrimental effects of nitrite poisoning. Pick up some aquarium salt and follow the directions for medicinal use. Don't forget to dose the replacement water according to it's volume during water changes, in addition to the tank dosing schedule.

Third defense: Prime can neutralize nitrite so it's not as harmful. With each water change, add a double dose of Prime. Make sure you have either an airstone or a HOB filter adding lots of air while double dosing Prime, as it consumes some oxygen in the reaction to neutralize nitrite.

Your nitrites should go down over time as you build up enough bacteria to handle your current fish load. You'll need fewer and fewer water changes, until you can go to a normal weekly 10% change.

 

[coldmachineUK]

Hi there

I agree with dskidmore in that water changes are your solution to the problem here. You will need to do them daily until things calm down, but I'm not sure I'd go as far as two 75% a day because the level of water change depends on the level of your nitrites. Some guideline figures: anything from 0.1-0.5 = around a 25% daily water change, anything from 0.5-1.0 requires a 25-50% daily water change, and anything above 1.0 requires a 50% daily water change and cessation of feeding until levels drop.
I would think changing 75% of your water twice in a day will actually upset the fish with the associated sudden changes in temp and pH etc unless you use a drip to re-add water. I know people regularly advocate large water changes, but IME with keeping sensitive fish like loaches I find it upsets them and exacerbates the existing problem.

The suggestion to add an airstone is also a good one: adding extra aeration will help relieve your fish who will be suffering from nitrIte poisoning.
I've actually been studying this in some depth lately on a scholarly level, and it is also now much more certain in my mind that adding aquarium salt is beneficial:

"Addition of some salt (NaCL, i.e. "rock salt", at a 3ppt to 8ppt concentration) to the tanks or transport vessels holding stressed freshwater fish minimises the osmotic gradiant (and consequently water and ionic diffusion rates) between the environment and the fish's plasma increasing survival" (Moyle & Cech, 2000). This is because when a fish is stressed water rapidly diffuses into the body and overwhelms the osmotic/ionic regulatory controls. It gets far more complex than this, but I'm citing this in support of dskidmore that adding salt will only be beneficial.

 

[dskidmore]

I was suggesting 2x75% as an absolute maximum, not a recomended routine. Change out the minimum you need to to keep your nitrites down.

 

[naitch1980]

That's great advice, thanks everyone

 

[naitch1980]

UPDATE! - Great news! My nitrites are returning to zero. Down to about 0.05 at the moment, but edging nicely, but slowly toward 0!

 

[dskidmore]

Good job! Keep it up!