After returning to the hobby I set up a single tank 25 gal cube, and used a lot of live plants and Co2. Early on, within the first month or two, I had bio-film on the water surface, but after adding some fish and with the tank maturing it didn't last very long. Maybe a week or two max.
I am hoping to add a few new fish to the main tank, so I got carried away and started a 10gal quarantine tank (qt). I put the canister filter for the qt on my main tank for about 3 weeks, and then put it on the qt for the long haul. After another month I added some simple plants, some watersprite, an amazon sword, and some monte carlo. With no fish in the tank, I have had an oily film on top of the water for a few months now. I change the water almost every other day, and try to siphon from the top of the tank, but the film just seems to persist.
I am at a point where I am ready to buy some new fish and use the qt, but this film has me slightly uneasy. So I guess I am wondering ... is this normal? and also, do some plants like watersprite, which seem to be growing like mad, tend to leave more of a film than other plants?
I was using the API water treatment with aloe for a while (stresscoat), but then started reading on this site, that it may not be great for fish. Either way I switched to api tap water conditioner about 2-3 weeks ago. I doubt the api stress coat is to blame here as I was using it on my main tank as well, and it never seemed to cause a film there.
So in summary, two tanks, slightly different plants, one with fish, one without. The fishless one continues to have any oily film problem and the other does not. Both use fluval canister filters, the same types of filter media, same gravel, etc. Maybe the only other difference is that i use an airstone on the main tank when the lights are off.
Any thoughts?
One other thing, I tried using the fluval attachment for skimming off the surface, but it was really finicky and oversized for the qt. I guess I could give it another shot, but it really seemed to be a piece of junk with rather inflexible hosing and just an ugly appearance.
I am hoping to add a few new fish to the main tank, so I got carried away and started a 10gal quarantine tank (qt). I put the canister filter for the qt on my main tank for about 3 weeks, and then put it on the qt for the long haul. After another month I added some simple plants, some watersprite, an amazon sword, and some monte carlo. With no fish in the tank, I have had an oily film on top of the water for a few months now. I change the water almost every other day, and try to siphon from the top of the tank, but the film just seems to persist.
I am at a point where I am ready to buy some new fish and use the qt, but this film has me slightly uneasy. So I guess I am wondering ... is this normal? and also, do some plants like watersprite, which seem to be growing like mad, tend to leave more of a film than other plants?
I was using the API water treatment with aloe for a while (stresscoat), but then started reading on this site, that it may not be great for fish. Either way I switched to api tap water conditioner about 2-3 weeks ago. I doubt the api stress coat is to blame here as I was using it on my main tank as well, and it never seemed to cause a film there.
So in summary, two tanks, slightly different plants, one with fish, one without. The fishless one continues to have any oily film problem and the other does not. Both use fluval canister filters, the same types of filter media, same gravel, etc. Maybe the only other difference is that i use an airstone on the main tank when the lights are off.
Any thoughts?
One other thing, I tried using the fluval attachment for skimming off the surface, but it was really finicky and oversized for the qt. I guess I could give it another shot, but it really seemed to be a piece of junk with rather inflexible hosing and just an ugly appearance.