I have a 55 gallon tank with 18 Zebra Danio. It has been up and running for two months with no problems. Every Sunday I vacuum the tank, replace two gallons of water and add a weekly treatment of Easy Balance and Stress Coat. This past weekend I added three more fish (bringing the total to 18), added additional automatic feeders and did my weekly cleaning. I noticed within hours the water became milky looking and has continued to get worse. I changed both of the water filters, made sure the pump was clear, checked the heater and added a water clarifier twice (which now I am hearing is not a good idea?) I thought there might be a dead fish in there but I can't find it and the zebra's zip around so fast I can't count to find out if one is missing. I do have automatic feeders but someone said I am over feeding them. I have 4 feeders that feed twice a day (total of 8 feedings) which I know sounds excessive but there are 18 fish and they go crazy eating when the food is released. I also don't get a lot of stuff when I vacuum. But I have done something wrong and I don't want my fish suffering. Any ideas of what I can do to fix the problem and what it is I am doing wrong? Am I overfeeding and how much food should 18 fish get? Any advice would be appreciated!
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- Thread starter michelle73
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Do you have a water test kit ? It could be a bacteria bloom of some sort, diffused organics from vacuuming the tank, do you have any type of air stone ?
What is your water temperature ? Without your water parameters it's hard to tell. A good test kit will allow you to check your Ammonia \ Nitrite \ Nitrate levels if you don't have one already, strips will work in a pinch, but it will not give you Ammonia unless you buy them separately, API Freshwater Master Test would be better.
I had to keep my 60 gal at 2 ppm of ammonia for several weeks before my tank moved to the second step in the Nitrogen cycle, with so few fish, and unless you've tested and seen Ammonia \ Nitrites spike it's possible it's just now cycling.
Also your fish feeding schedule, while twice a day may be fine, you may want to hand feed them to see how much they are actually eating in a 2 minute period, and make sure they do not receive more than that. Generally their stomach is about the same size as their eye, any more than that and they are being overfed, which will cause them to produce excess waste, increasing ammonia levels, if your tank isn't fully cycled then that could be causing some of the problem.
What is your water temperature ? Without your water parameters it's hard to tell. A good test kit will allow you to check your Ammonia \ Nitrite \ Nitrate levels if you don't have one already, strips will work in a pinch, but it will not give you Ammonia unless you buy them separately, API Freshwater Master Test would be better.
I had to keep my 60 gal at 2 ppm of ammonia for several weeks before my tank moved to the second step in the Nitrogen cycle, with so few fish, and unless you've tested and seen Ammonia \ Nitrites spike it's possible it's just now cycling.
Also your fish feeding schedule, while twice a day may be fine, you may want to hand feed them to see how much they are actually eating in a 2 minute period, and make sure they do not receive more than that. Generally their stomach is about the same size as their eye, any more than that and they are being overfed, which will cause them to produce excess waste, increasing ammonia levels, if your tank isn't fully cycled then that could be causing some of the problem.
Oh, thanks! I will pick up one of the test kits today. I had never even heard of a air stone so I will try and find one of those as well. I keep the water temp at 78. I think I may have been over feeding as well. I know its silly but I don't want them hungry. I did cut the feedings from 8 down to 6 and the water has made a small improvement. I will go ahead and remove the other automatic feeders and pay closer attention to how much they are eating. Thank you for responding and for the tips!
Any amount of ammonia and/or nitrite about zero can be deadly to fish. Anytime you test and get a reading higher than zero (when you already have fish in your tank) you need to do about a 50% water change and you would need to do that daily until you get it down to zero. Your goal is ammonia 0, nitrite 0, and nitrates about 20ppm. Oh, and welcome to this forum!!
IMO you are feeding these fish 3x more than you need to. That's probably contributing to your water quality issues. Keep in mind fish can go a looong time without food. Like weeks.
I'm not sure about any of the water additives you've mentioned, but there's no need for anything other than a dechlorinator. I'd stop with the additives.
Like said, you need a water parameter test kit for monitor for ammonia, nitrite and nitrate and you should do weekly water changes of 10% at a minimum. Many of us do more than 10%.
All that aside, good call on using zebra danios to establish your tank. They are very hardy fish, ideal for this. I commend you for tolerating 18 of them! I've got 4 in my 55g and they drive me nuts.
I'm not sure about any of the water additives you've mentioned, but there's no need for anything other than a dechlorinator. I'd stop with the additives.
Like said, you need a water parameter test kit for monitor for ammonia, nitrite and nitrate and you should do weekly water changes of 10% at a minimum. Many of us do more than 10%.
All that aside, good call on using zebra danios to establish your tank. They are very hardy fish, ideal for this. I commend you for tolerating 18 of them! I've got 4 in my 55g and they drive me nuts.
lol...freshyfresh. I will cut back on the feeding. 
To be honest I started with 5 zebra danios and every week or so I would get 5 more. I had 20 but did lose two about three weeks in. I kept with the zebras because I was afraid to add anything different. I didn't know what would get along with what. But I do love them and they are fun to watch. I have to really watch when I try to vacuum the tank because they are curious and try to swim closer than I would like.
I want to thank everyone for taking the time to offer so many helpful tips.
To be honest I started with 5 zebra danios and every week or so I would get 5 more. I had 20 but did lose two about three weeks in. I kept with the zebras because I was afraid to add anything different. I didn't know what would get along with what. But I do love them and they are fun to watch. I have to really watch when I try to vacuum the tank because they are curious and try to swim closer than I would like. I want to thank everyone for taking the time to offer so many helpful tips.
If you have cloudy water even after changing the water, you probably have a bacterial bloom. I had one of these and I panicked. I was afraid I was going to loose all my fish. I did water changes every day. After about a week, the water cleared up and everything was fine. You only want to add a couple of fish at a time. I have a 90gal tank and 4 fish at a time is my limit. You have to wait for the water to adjust to the addition and the bacteria to catch up. Adding too many fish at one time will cause a bacterial bloom and throw off the parameters. Ideally, you are only supposed to add 2 to 3 fish at a time and then wait a few weeks before adding any more. Its hard to be patient, because you want all the fish you can have right away. But, patience is the key to everything in aquarium world Hope all is going well with your tank now.
Hope all is going well with your tank now.
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I started changing 10 gallons a day and only doing two feedings a day. It is still cloudy but is showing some improvement. There is more to getting a tank healthy than I thought. I am so naïve. I thought I was right on target starting it up. I researched stuff on line and talked with the staff at the pet shop and really thought I was doing right. I am just glad I found this site and everyone here is so helpful.