residue on surface

[Andrew52984]

Hey this is a totally dumb question. My 46g tank is suddenly having a oilly surface residue since adding a Korallia 2 powerhead and starting to feed my fish mysis shrimp. Is this from not enough flow skimming the suface, the Korallia 2 powerhead points more at a 45 degree angle toward the middle of the tank and the flow from the marineland c220 canister filter points downward also. Should i aim the filter flow more towards the surface? and I also just purchased an aquac remora skimmer with the maxijet 1200 yesterday, can't wait to get it! Thanks for any input.

 

[BigJay]

out of curiousity are you running carbon or due for a change out?

 

[vdituri]

This is common in tanks without sufficient surface water agitation.
The skimmer may help out.
It's a combination of things, but mainly just organic stuff like oils from the fish foods etc.

Try an airpump with an airstone in a corner of your tank. It helps clump it together with the bubbles kind of like a SUPER simple skimmer. If you get some foam on the surface you can just spoon if off and throw it away.

Tanks with overflows don't have this issue normally as the gunk flows down into the sump and gets skimmed out.

 

[fatman]

You definitely do not want to get the surface organic laden water to release the organics bak into the lower waters depths, so do not aim a powerhead at the surface. It would allow the increased exchange of carbon dioxide and oxygen at the waters surface better without the oily layer, but you want to encourage the oil into goig to the surface so that it can be removed. As mentioned this is typically done by a suface skimming overflow. This sends the oily disolved organic compounds down to a skiimer typically for removal from the water. There are continual arguments/disagreements and discussions about the use of GAC for this and I wont get into that here. But if you do have an overflow and no skimmer I would definitely consider using GAC. If you have no overflow and do not have a sump in immediate plans for the future you might want to consider some type of small canister filter or a phosban filter for the use of GAC for removing the surface layer of dissolved organics that naturally occur in a tank.

 

[Woodstock]

Hey this is a totally dumb question. My 46g tank is suddenly having a oilly surface residue since adding a Korallia 2 powerhead and starting to feed my fish mysis shrimp. Is this from not enough flow skimming the suface, the Korallia 2 powerhead points more at a 45 degree angle toward the middle of the tank and the flow from the marineland c220 canister filter points downward also. Should i aim the filter flow more towards the surface? and I also just purchased an aquac remora skimmer with the maxijet 1200 yesterday, can't wait to get it! Thanks for any input.

I think you'll really like the Remora skimmer. If you have room, get the skimmer box that comes with it. The 'box' is acrylic and has teeth at the top. You can adjust the height so it skims the water's surface very well.. the pump sits down inside the box.
If you don't have room for the box, the skimmer itself may take care of your excessive organic issue (slime at the top of the water).
You can also get a papertowel and lay it on the surface for a few seconds to clean it up... I've heard some people use human hair also.

 

[fatman]

Darn i jumped the gun again and apparently did not read all of the first post. Your canister filter is not skimming the surface water into its inlet as it is probably below the surface without a skimmer box enclosing it. The skimmer box accessory for the skimmer would be a huge improvement over using the skimmer without it. Skimmer boxes can easily be home made. Basically all you would be doing is providing a box of some sort that the inlet pump would fit into that would extend to just above the waters surface. This box would then have slots cut in it to allow just the surface water to flow in to the box, meaning the slots need typically only go to a level of approximately 3/8 or 1/2 inch below the waters surface. Plastic wire ties work good for holding the box to the pump. with a skimmer box the surface layer of oil will quickly disappear.

 

[Andrew52984]

Wow, thanks for all the responses very useful and very encouraging. I'm very happy to hear that the skimmer should help once i get the box which i will add very soon. Thank you for all the help! I'll post another update once i get the skimmer.