Oily Layer

[Tazzy]

Hi there...I am new on this sight as i am in distress! I have had my tank about 2 years so not all that new, however my knowledge is very limited. for the past few months i seem to be getting an oily layer on top of the water which i usually scoop off with a spoon and then it'll be fine for a few days and then the layer will be back again. Also i bought some tetras last week...4 of the tetras have died...and so has my siamese fighter, which was originally in the tank..i am now left with 3 fish!!!!! and i think i have another tetra on the way out. i have done several water tests over the past week and water conditions are perfect. The symptoms of the fish that have died all seemed to start slowing down or just lying on the bottom of the tank until they die. there were no visable marks/growths/worms etc...from the outside they looked perfectly healthy...CAN SOMEONE PLEASE HELP!
thanks
tazzy

 

[rdd1952]

Hello and welcome to the forum.

Lets talk about the oil first. Some water supplies (mine is one of them) are prone to a film on top. I still haven't found out what causes it but my water does the same thing. I can leave it standing in a bucket for a few days and get the same thing so I know it isn't anything in my tank. I will say however, that you can also get a film if you put your hands in the tank with oil or grease or even hand lotion on them. There a couple ways to keep in off. You have found one already but it is time consuming and never really worked well for me. If you have a HOB filter, you can lower the water level slightly so that the waer splashes back into the tank. That will keep the film broken up. Or you can add airstones to the tank. The air bubbles breaking the surface should also keep it broken. That is the option I use.

Now lets get to the more important matter of your fish. Since you have had your tank for a while, we can probably rule out in not being cycled but I will ask if you have checked your ammonia and nitrite levels to make sure they are 0? It's possible that ading the tetras last week cold have caused an ammonia and/or nitrite spike if you only had the betta in the tank before. How large is the tank and what fish were in the tank before you added the tetras?

If it was a pet store betta, 2 years is a fairly typical life span for them. As they get old, they usually do exactly what you described, laying in one place on the bottom or under a plant for a few weeks until they pass on. They also seem to have some swim bladder issues and can't stay upright or have trouble getting off the bottom to go to the top of the tank.

Having said what I did about the water and film earlier, since you only started seeing it recently, it could well be that you have gotten something in the tank that has caused it and subsequently is killing the fish. If so, the betta would be particularly at risk since he is a surface breather and would be picking up whatever it is everytime he goes to the top to breath.

Also, how did you acclimate the new fish? It could be that the pH/GH/KH of the fish store ater was considerably different from your tank and the new fish suffered from such a sudden change.

Sorry for all the questions but the more information, the easier it is to find a solution to the problem.

 

[Tazzy]

Hello and welcome to the forum.

Lets talk about the oil first. Some water supplies (mine is one of them) are prone to a film on top. I still haven't found out what causes it but my water does the same thing. I can leave it standing in a bucket for a few days and get the same thing so I know it isn't anything in my tank. I will say however, that you can also get a film if you put your hands in the tank with oil or grease or even hand lotion on them. There a couple ways to keep in off. You have found one already but it is time consuming and never really worked well for me. If you have a HOB filter, you can lower the water level slightly so that the waer splashes back into the tank. That will keep the film broken up. Or you can add airstones to the tank. The air bubbles breaking the surface should also keep it broken. That is the option I use.

Now lets get to the more important matter of your fish. Since you have had your tank for a while, we can probably rule out in not being cycled but I will ask if you have checked your ammonia and nitrite levels to make sure they are 0? It's possible that ading the tetras last week cold have caused an ammonia and/or nitrite spike if you only had the betta in the tank before. How large is the tank and what fish were in the tank before you added the tetras?

If it was a pet store betta, 2 years is a fairly typical life span for them. As they get old, they usually do exactly what you described, laying in one place on the bottom or under a plant for a few weeks until they pass on. They also seem to have some swim bladder issues and can't stay upright or have trouble getting off the bottom to go to the top of the tank.

Having said what I did about the water and film earlier, since you only started seeing it recently, it could well be that you have gotten something in the tank that has caused it and subsequently is killing the fish. If so, the betta would be particularly at risk since he is a surface breather and would be picking up whatever it is everytime he goes to the top to breath.

Also, how did you acclimate the new fish? It could be that the pH/GH/KH of the fish store ater was considerably different from your tank and the new fish suffered from such a sudden change.

Sorry for all the questions but the more information, the easier it is to find a solution to the problem.

i have a 20l tank..not sure what that is in gallons. I had the fighter for about 6 months. I have a sucking loach, not sure exactly what kind...(as you can see my knowledge is poor) and about 5 months ago I bought about 5 tiger barbs who seemed to die off slowly until 2 were left and then those 2 were fine. until recently when they both died..then i left the tank for a while and last week i added tetras and a albino corydoras. I already had one albino corydoras so had 2 in total....and the first one died last week and now today the 2nd one has died. so now all that's left in my tank are 3 tetras and the loach. i did a water test today all the levels are what it should be, the water is perfect and temp is about 25. my fish always seem to die until i have 3 or 4 left in the tank then they seem to stay like that and as soon as i want to add a few more they start dying again. i got my fish for the local pet shop, however i don't think they are fish specialists as it just the local store. I kept the bag i bought them in in the tank for about 10 minutes then added a little bit of my water and left it a bit longer and so on (i was beginning to think it has something to do with the way i add fish?). i didn't throw any of the pet shop's water in my tank. the film on the top was there before but seemed to disappear and now it's back. my hands are always clean before i stick them in the tank. sometimes if i don't clean the film off it can get so bad that if i throw food in the food just stays right there...but i will definately try what you do and move the filter. I was also thinking about getting an airstone for the tank so maybe i'll give that a go as well. hope my answers will help...

thanks
tanja

 

[rdd1952]

I think the film is strictly a product of the water company and you will have to deal with it via skimming or something to create a surface disturbance. As for your fish deaths, I think it is because your tank is too small. At 20l, your tank is only slightly over 5 gallon. For a tank that size, you can really only have 3 or 4 small fish. When you add new fish, you are putting a strain on the filter and the bacteria colony can't catch up. The tiger barbs could have quite possibly harassed some of the fish to death too as they are not good community fish and will pick on almost any fish.

Also, if at all possible, find some that you can give the loach to. Most likely, it isn't a loach at all but actually a Chinese algae eater. They can grow to 6" long and become very aggressive as they get older. They will try to suck the slime coat off other fish and have been know to attack corys and suck their eyes out (never seen it done, only read about it).

 

[Tazzy]

I think the film is strictly a product of the water company and you will have to deal with it via skimming or something to create a surface disturbance. As for your fish deaths, I think it is because your tank is too small. At 20l, your tank is only slightly over 5 gallon. For a tank that size, you can really only have 3 or 4 small fish. When you add new fish, you are putting a strain on the filter and the bacteria colony can't catch up. The tiger barbs could have quite possibly harassed some of the fish to death too as they are not good community fish and will pick on almost any fish.

Also, if at all possible, find some that you can give the loach to. Most likely, it isn't a loach at all but actually a Chinese algae eater. They can grow to 6" long and become very aggressive as they get older. They will try to suck the slime coat off other fish and have been know to attack corys and suck their eyes out (never seen it done, only read about it).

GROSE!!! possibly a chinese algae eater...the bloke in the shop said it was a loach so i am just taking his word for it. My loach/algae eater keeps to himself...he is even too shy when i come around. as soon as he sees me he darts back into the little shipwreck. so he is no problem...however i might see if i can get another fighter and then just leave the tank at that. Otherwise the tank looks really dull and boring. I would love to have a really big tank, but my flat is only just a bit bit bigger than the tank itself! so will have to wait for that. thanks for your advice really appreciate it and don't so feel as though i have murdered my poor fish. still it's all learning curves!

tanja

 

[rdd1952]

One a side note, I see your "Group" is "Validating". In order to be able to post in all the forums, you will need to find the email you should have received when you registered and click the link in it to validate your membership. If you didn't get it, check your spam folder and make sure you can receive email from gmail.com. You can have the email resent by going here.