Oily Surface Again

[Bluetooth]

Hi Guys

As some of you will recall i made a thread about a month ago regarding a little issue i was having with my water.

The basis of the issue was the surface of my water was getting oily, i removed the top covers of my tank and the issue went away. After it went away i constructed a DIY reflector from kitchen foil on the top flaps, once they went back on he tank the oily ness has come back.

No issues with my stats, no deaths, no gasping, no dead plants, o2 transfer is running fine, discus breathing is at 66 per minute.

Anyone got an idea what the oily surface can be? im not overly worried as there arent any water issues atm im worried it could turn into something though.

Thanks all.

[RD.]

The correct term for the "oil slick" that some people experience in their aquarium, is neuston.

http://aquariumalgae.blogspot.com/2007/06/as-we-can-see-in-this-article-algae.html

http://www.skepticalaquarist.com/docs/biofilm/surscum.shtml


Looks like oil, but is typically protein based. Overfeeding, and/or poor circulation or surface tension is usually the cause. If you have to get down on your kness & look up, squint your eyes at a 40° angle to get the light just right, just in order to see it, chances are it isn't going to cause you or your fish any serious issues. :)

[Bluetooth]

Hrm, ive read both those links and it doesnt sound like what is described, i will take a pic the next time i feed if i can get it to photo as the light above will most likely block it out.

I have 2 spray bars working in te tank at water level so i dont think its this nuetson thing.. ill try to get a pic as mentioned however the paper towel thing might solve it.

[RD.]

The examples shown & described in the links above are rather extreme.
In a minor case of surface film what one typically sees is just a very light
film that appears to be a light oil slick.

[Bluetooth]

Ah ok well in that case it could be what you mentioned then as that is how it looks.

[rickztahone]

do you feed beefheart?

[Jhhnn]

During water changes, I routinely use the siphon tube to create a surface vortex, suck the film away in my one tank. My other tank has a wet/dry overflow filter, never shows any surface scum at all.

Some aquarists use these on the intake of power filters to accomplish the same ends-

http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=12703

The toothed clear plastic part floats at the water surface, and the ratio of surface to deeper water is adjustable. I've never used 'em, preferring to use a prefilter sponge on my canister filter.

[Bluetooth]

do you feed beefheart?

Sparingly, probably 1 frozen cube per week if that, mostly tetra prima or hikari discus gold

Yesterday i took my cover flaps off the tank to give them a clean and when i turned the rear one over the DIY reflector i had made out of tin foil stuck to the underside of the flat is covered in some kind of chalky green substance, the water dripping from the reflector was milky and i cannot clean the reflector the substance will not come off.

This is odd... the water tests fine, fish are fine and plants seem to be doing ok but this scum stuff worries me

[daboo]

Yesterday i took my cover flaps off the tank to give them a clean and when i turned the rear one over the DIY reflector i had made out of tin foil stuck to the underside of the flat is covered in some kind of chalky green substance, the water dripping from the reflector was milky and i cannot clean the reflector the substance will not come off.

Bluetooth,
I am trying to figure out where your reflector sits. Are you saying you attached it to the underside of your aquarium cover so it is in close proximity to the water surface? If so what would be the purpose of this reflector?

If it is as I describe I would not want a substance like that hanging "in exposure" with the aquarium water. I just leave the glass covers on my aquarium since it is inert unlike hanging metal right over the water.
Karl

[Jhhnn]

The chalky green stuff is a separate issue- probably a mixture of algae and corrosion of the reflector... algae is amazing stuff, the bedrock of life on the planet, persistent and adaptable in the extreme...

I really like the commercial glass tops, regardless of the lighting. They control evaporation effectively, keep fish in and other stuff out. Prices are reasonable online, too...

[Bluetooth]

The tank is quite dark as im only using 18w t8 lights and i wanted to brighten it up a bit so i took some food safe tin foil and used aquarium sealent to secure it onto the plastic flaps, the flaps cover the tank. I dont have any cover glasses as the tank is a juwel trigon and only has the light bar and 2 plastic cover flaps.

I dont have any huge issues with evaporation while the covers are on, however if i remove the flaps, evaporation sets in quickly lol.. suppose its one way of doing water changes =-)

[daboo]

I assume the T8 lights are what came with the aquarium? If you wanted it brighter how about replacing the light with high-output T5 lights?

Because of the complications you are seeing with the foil I wonder whether you really want it up there. Who knows what might be growing in that gemisch.

BTW - evaporation is not the same as water changes. You will be concentrating electrolytes unless you add RO or DI water.