Dying Fish

Hi Gaynor,

sorry about your fish. It's horrid when they die and you don't know why.

can you tell us a bit more, such as what your water readings are ( perfect to a shop worker may not be perfect to your fish!!) what fish you have, how long you've had them and what symptoms you've seen, if any?

Also good to know your water temp, whether you have live plants and what your substrate is. Basically as much about your tank as you can tell us. this gives us a chance to work through possible causes and solutions.

FC76

In your first post, you say you have a new filter. May I ask when you changed it and what you did about cycling the filter medium. If you just hoicked your old filter out and replaced it with a new one, media and all, this is where your problem lies.

And 'within the required parameters' is meaningless as there is only one good value for ammonia and nitrite, and that's zero. Anything other than zero is not good.
I would seriously consider buying your own test kit. A liquid reagent one with test tubes rather than strips. On-line is cheaper. If you get samples tested at a shop again, ask them to write down the numbers.

In the mean time, my thought was the same as Steve's. If you have just replaced the whole filter, media and all, you need to do a lot of water changes as you'll be in the middle of a fish-in cycle. You need to stop ammonia and nitrite ever getting above 0.25.
The bacteria treatment is unlikely to help unless it's Tetra Safe Start and even that won't work if it's been handled incorrectly during its transit from the factory to your tank.

You mentioned using something to correct for hard water - can you tell us exactly what that is please? I've not heard of anything for correcting hard water, though I do know there are chemicals to lower pH - and use of those is not recommended.

my old filter was very basic and on it's way out, hence the change but my first fish died before the filter change???  I will look to get a better testing kit though. my ammonia was zero apparently and no idea of the number for the nitrates.   I've already done one partial water change and the bacteria infections treatment is Melafix, the remaining fish now seem to have perked up though which gives me hope.  The Water Conditioner treats chlorine and neutralises heavy metal, not hard water (my mistake - sorry).  It's by Aqua Care and I've used it from the start.  I did wonder if the tank was over stocked including the two small plecs I had 17 fish??  I've been using PURE capsules which I have added to the filter and placed in the tank.  I cleaned my gravel about 8 days ago.  The new filter is a Fluval and has 3 separate cartridges inside.  Think I will have to see if they survive the night, if they do then hopefully things will continue to improve.  It's so hard, knowing a little bit but actually not very much so thank you so much for all your messages.  Can anyone actually recommend a tester kit please?

thanks for that info Fishcake76,  You will be pleased to hear there have been no more deaths.  I was dreading this morning but they all seem fine.  I have to continue with the Melafix treatment for 6 more days but will get the API liquid tests for future checking, I already have the quick test strips.  The relief I feel right now is unbelieveable.  Thanks so much for your help 

OK, amateur alert. What is media?? Sadly I didn't keep the old filter which had a sponge insert, this new one has cartridges but there was nowhere in it to put it in the new filter as they are very different.  I got an all in one aquarium to begin with and the filter was basic, the new one is a better quality one.  how long does a 'fish-in' cycle take??

EDIT - typed this at same time as sue typed her reply but have left it as it was!

Media refers to the sponge/cartridge that is in your filter. This is what the good bacteria that you want grow on. they also grow on the tank glass and in the substrate and on your decor but the filter is their main breeding ground.

Read sues fish in cycle article it will tell you all you need to know. Steve has put a quick link in his reply (i don't know how to do that!!!!)

To quickly answer you're question tho, it could take weeks or months. Due to the amount of fish you have you will have to be REALLY on top of you're ammonia and nitrite readings, keeping them at 0 if you can but never letting them go above 0.25. If this means daily big water changes then that is what you'll need to do. the fish will be more stressed by swimming in toxic water than by daily water changes.  If you let it build up, you will most likely lose more fish.

If you can bear it, then it might be an idea to try and reduce the amount of fish you have in your tank and i would start with the loaches and the plecs as they need  a much bigger tank than you have. They may be little cuties now but they grow into monsters!!!!! Try speaking to the shop you got them from and see if they will take them back but don't be surprised if they wont as you have had some deaths so they may be reluctant to risk the chance that it is actually a disease.

Other wise you could try advertising them but please make sure they go to someone who knows what they are doing!!! 

You could also consider getting a bigger tank!!!!!!!  Make sure you cycle it before you put fish in tho!!!!! 

Steve is quite right, I'd missed the bit about the tank being 18 months old 

So cycling a tank is like when you first get a new one and you set it up but don't put the fish in until the water is 'right'. 

Actually, cycling a tank is the process of growing bacteria. They need a source of food to multiply, in this case ammonia for the first species of bacteria. This comes from either a bottle of ammonia solution (fishless cycling) or from fish (fish-in cycling). If no fish are put in a brand new tank, then just letting it run does not cycle it because no fish = no food for the bacteria. But if ammonia solution is added to this empty new tank, there is food and the bacteria will grow.
Once the first species, the ammonia eating bacteria, start to multiply they turn the ammonia into nitrite. Nitrite is the food for the second species of bacteria and now they can start to multiply too.
It takes several weeks for both species to multiply enough to cope with the waste from a tankful of fish.

The majority of these bacteria live in the filter. It is in the dark and the water flowing through it brings a constant supply of food and oxygen. They live in the biofilm, which is attached to every surface in the tank - that white cloudiness you get on the glass and have to wipe away to see the fish properly is biofilm. The bacteria do grow in the biofilm on the glass, the decor etc, but not as many as in the filter.
This is why you have to be very careful about the stuff inside the filter (the media) as it is stuffed full of the good bacteria. If you throw it away, you have to grow a lot more bacteria. This is why we were all worried about you throwing away your old filter, complete with its media and bacteria. Because the tank has been running so long, there will be a good number of bacteria on the surfaces in the tank, just not nearly enough of them for the fish in there. But as Steve pointed out, getting the bacteria to start growing is the slow bit. You already have some, so it won't take as long to colonise the new filter as it does with a brand new tank.

You do need to monitor both ammonia and nitrite and do water changes as often as necessary to keep the levels below 0.25. Once they stay at zero by themselves, you can go to weekly maintenance water changes.





You do really need to look at your fish though. You say the plecs are fully grown - bristlenoses grow to 10 to 12.5cm. Zebra loaches need a tank 120cm long. Golden gouramis (a colour morph of the three spot gourami) need a tank at least 90cm long. None of these are suitable for a 65 litre tank, I'm afraid.
The cherry barbs and neons are fine though.

Update for all those who helped.  No more deaths and my tank seems fine.  Got the API Water tester so I can get more accurate results.  I did have the Aquatic Centre check again and my Ammonia was 0.05, Nitrites 0.05 and my Nitrates were at 1.  I am very relieved