My fish die after a tank clean - Tropical Fish Keeping - Aquarium fish care and resources
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post #1 of 11 Old 09-18-2012, 03:27 PM Thread Starter
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My fish die after a tank clean

I need some help with my new aquarium. I got a new 45 litre aquarium in May and set this up using Interpet New Aquarium Start-up Kit. I left this for approximately 2 weeks before I added in some fish. I carried out PH and Nitrate tests and all were ok. I added 5 harlequins and left them for further 2 weeks before adding 8 neon tetras. All was well with this and I had no initial problems. After 4 weeks, I carried out a gravel clean and a 25% water change. The next morning there were 2 neons which had died. All was well for a further 4 weeks and I carried out another clean and water change. This time the next day, 3 harlequins had died and 1 neon. Again, all was fine with the fish for the rest of the month and after another 4 weeks and another 25% water change, 1 harlequin and 1 neon had died.
So after adding 8 harlequins and 5 neons in June, I am now left with 1 harlequin and 4 neons. I have no problems until it is time for a tank clean and water change. I know that I must be doing something wrong but I am not sure where I am going wrong. I regularly carry out tests and the both PH and nitrate are always fine. I always add fresh start when adding in new water and make sure that the PH is at the correct level. Any advice/help would be much appreciated as I am really reluctant to add any new fish until I know where I am going wrong.
When carrying out the water change, I am cleaning the filter. The bubbles in the filter have previously stopped working and did not start again until such time as I cleaned the filter. I read that this should only be done gently when carrying out a water change.
Further Information I also have an algae problem. On the last clean, I washed the gravel and the ornaments but it has come back less than one week later. Not sure if this is in any way connected or a separate problem.
Please help I am starting to get disheartened by it and I really love my tropical fish.
Thank you all in advance
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post #2 of 11 Old 09-18-2012, 05:01 PM
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Originally Posted by sarahlouise View Post
When carrying out the water change, I am cleaning the filter. The bubbles in the filter have previously stopped working and did not start again until such time as I cleaned the filter.
I think this might be the problem.. the point of a water change is to lower the nitrate concentration. It's essentially a dilution. When you clean the filter, you remove some of the helpful bacteria that processes the ammonia and nitrite. This might cause the ammonia and nitrite to spike and kill the fish for the first few days, until the bacteria colony grows back
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post #3 of 11 Old 09-18-2012, 05:02 PM
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Hello Sarah! Welcome to the forum - and fishkeeping!
Sorry that you've been having such a difficult time. . . lets see if we can figure out where the problem is. . .

There are a couple of things that I'd like to know about the process you go through during your water changes...

First, I'm not familiar with the product called Fresh Start, but you must be sure to add something into the water that will remove all traces of Chlorine, Chloramine, and heavy metal toxins before you put it into the tank. Is this what Fresh Start does?

Second, are you making sure that the temperature of the water going in is the same as what is in the tank already? It's very important to do so, as a rapid change in water temperature can prove fatal for the fish.

As a general rule, water changes should be done every week - not every other or once a month. Are you doing them once a week, and only having problems during some water changes?

You mentioned keeping your Ph at the correct range with the use of Fresh Start. I've found that using chemicals to keep Ph within a desired range is seldom the best way to go about things. What tends to happen quite often with this method is that the Ph will shift suddenly, usually when the chemicals are being added, and this is very stressful on the fish, and deadly. . . there are ways to safely harden or soften your water, but the best way to stock a fish tank is to choose fish that are ideally suited to your tap water in the first place. It's easier, cheaper, and all-around the safest way for everyone involved!

You mentioned testing your water, but you only specifically speak of the Ph and Nitrate levels. We usually look at Ammonia and Nitrite first, as any trace of these in the water are very dangerous to the fish... oddly enough, to fish that have become used to living with trace amounts of these toxins, the sudden removal of them from the water can also stress their systems enough to cause harm. If you don't have one already, I strongly recommend that you purchase an accurate liquid testing kit (with vials and chemicals), and check out the levels for ammonia and nitrite as soon as possible. I'm not entirely sure where in this world you are located, but here in the States the Freshwater Master Testkit by API is the most highly recommended one.

Here is a link on the sticky on this site called A Beginner's Guide to the Freshwater Aquarium Cycle. If you aren't very familiar with the nitrogen cycle, I HIGHLY recommend you give it a read! The cycle is crucial in keeping healthy fish in a closed system. It can be a bit mind boggling at first, so please feel free to post any questions you might have!

Because of the bacteria that is necessary to have in your tank, it is not recommended that you should ever remove the gravel and clean it, as this beneficial and necessary bacteria lives on the surfaces inside of your tank - the gravel being a main one. If you clear away the bacteria, you can cause the toxins in your tank to spike, which. . . you guessed it! Can harm the fish. . . this is also why the PP is concerned about how you're cleaning out the filter. If/when you must clean the filter, you are correct in that it should be gently done (so as not to disturb the bacteria) but it also must be done in dirty tank water for the same reason.

As far as algae is concerned, usually algae becomes a problem if your lights are kept on for too long, but also if there is a high phosphate level in the tank. Phosphates, essentially, are wastes. If you aren't doing a water change every week, this will certainly contribute to the algae problem, as it gives it a source of nutrition that will allow it to thrive. I'd start by cutting back on the amount of time that the lights are left on, and we'll go from there.

This probably sounds pretty overwhelming!!! I'm sorry for that, but don't worry! There are lots of experienced fish keepers on this site who will be happy to help you set things right for your fish's health! Many of us (including me!!!) started off on the wrong foot, it's a lot to learn, but worth it for a tankful of happy, healthy, thriving fish!

Last edited by Chesh; 09-18-2012 at 05:05 PM.
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post #4 of 11 Old 09-18-2012, 09:03 PM
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Welcome to the forum. Chesherca is right, and we need just a bit more information to help you with your problem, and starting with a test kit is the way to go.

Never too far from crazy

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post #5 of 11 Old 09-18-2012, 10:36 PM
I am wondering if you are taking the time to ensure that the new water is a similar temp to the temp in your tank. Also you are likely creating spikes in certain things by wiping your bacterial colony.

The only thing you should clean with your filter is the intake time to time, and or make sure the media basket (if it has one) isn't clogged. Even then you can use old tank water and a tooth brush and make sure the little holes are open.

Algae problems are often related to one of a few things. A: too much nutrients caused by over feeding, B: tank lights are left on too long (Only need 8 hours of strong light, don't leave the lights on 24-7!), or ambient light from a window. If the tank is located near a window try to block out the light from it so it isn't reaching your tank.
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post #6 of 11 Old 09-19-2012, 10:25 AM
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I think is too much cleaning. I never change the filter, vacuum the gravel, clean the ornaments and change the water in the same time.
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post #7 of 11 Old 09-19-2012, 10:59 AM
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Originally Posted by corina savin View Post
I think is too much cleaning. I never change the filter, vacuum the gravel, clean the ornaments and change the water in the same time.
I agree with this.
Also have come to understand that some folk's remove fish from the tank when performing water changes,filter cleaning,vaccuming etc.
Should never remove the fish unless moving them to sick tank ,or removing them after they have died.

The most important medication in your fish medicine cabinet is.. Clean water.
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post #8 of 11 Old 09-19-2012, 02:40 PM Thread Starter
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Thank you all very much for your advice on this. I am grateful for any advice I can get. I will not be adding any more fish until all of my current problems are resolved. I am currently doing my water changes 4 weekly but I now understand that I should be doing these daily until I am on track and then carrying out weekly water changes from there on. I do not think that I have been getting the water at the correct temperate before adding to the tank. I will do this from now on. I use filter start and fresh start. I also started to use API PH instead of fresh start after my initial few problems. I am now aware that I am cleaning the filter wrong. Next time it needs cleaned (which after reading previous posts wont be for a while) I will gently rinse it in the tank water removed from the tank.

I now think that the algae is connected to too much light. The light is on in the tank for between 10 and 12 hours. I will reduce this and see if there are any improvements. The current algae is green. I have not had any brown.

Perhaps I am overfeeding which wont be helping with the algae and the filter becoming blocked.

I have a gravel hoover thing which I have used to clean the gravel. I have only removed the gravel and the ornaments once last week after the algae was so bad.

From here, I will buy an ammonia kit and stress coat. I will make daily water changes. I will also reduce the amount of hours that the tank light is left on.

Should I be doing anything about the algae that is currently in my tank? It is currently on the gravel and the ornaments. I used lovefish hair algae treatment but Im not sure if I should be using this it didnt appear to make any difference.

I will keep you all posted on my progress following my trip to the pet shop at the weekend to be prepared for the task ahead of me! I will get there.

Thanks again!
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post #9 of 11 Old 09-19-2012, 03:32 PM
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sounds like your on the right track now, go for the API MASTER TEST KIT, it seems expensive at first but you get alot of tests out of it and you want something that will test for ammonia, ph, nitrties and nitrates. I use API TAP WATER CONDITIONER and it works well. when you get your test kit its a good idea to test your tap water as well so you know what chemicals are in the tap water too. water temp is very important too make sure the new water is as close as possible.

As for the algae just try to reduce light and feed less, its actually common practice for alot of us to skip feeding completely once or twice a week, I feed 3 days then skip 1. You can clean of the decorations for now try to get algae under controll before cleaning all the gravel, I also try to use as few chemicals as possible. good luck and we look forward to your progress
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post #10 of 11 Old 09-19-2012, 10:53 PM
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I agree with Hanky. . .

Glad to hear you're figuring out where your problems are, and busy getting things set right! You've been given a lot of good advice here, and I'm certain that your fish will be fine once you get everything sorted. Good luck! Please keep us posted!
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