Surface slick

halcyon_diver

New member
ive got a 180 w/dual overflows, ive noticed over the past couple of days that the surface water seems to have a "scum slick" . Thought it might be my skimmer not keeping up, after my water change it cleared, within 2 days its back. I did notice that in the overflow area the water is pretty stagnant, i have a mag 18, 2 HK 3s- 2 HK 4s, and a couiple maxi 1200 stirring up the surface, it just seems that the water isnt getting skimmed from the surface, do i need to adjust the water level? any ideas?
Thanks
 

camarojweed

New member
Your overflow should be pulling this off, if your overflow height is the same as the tank height this layer will stay on the surface and not get pulled off.
 

fishieness

New member
you would have to increase the amount of flow that your pump is giving which would require adjusting the plumming if not getting a new pump.
Also, if you noticed it disappear after water changes, changing your carbon should help.
 

halcyon_diver

New member
ive got a mag 18...its putting out plenty of flow...i think camarojweed was right about it not skimming the surface enough.just need to know how to adjust the water level.
 

halcyon_diver

New member
no..not at all....return piping is 1" and the drain is 1 1/4" i tried adjusting both the drain and return with the ball valves and all it does is make the level in mthe sump rise. both return and drain seem to have great flow
 

camarojweed

New member
If anything you would want the level in the overflow to go down alittle bit so that way the surface layer is pulled off by the overflow...make sure that the pumps you have pointed towards the surface point toward the overflow, that should help too...
 

fishieness

New member
<a href=showthread.php?s=&postid=12850964#post12850964 target=_blank>Originally posted</a> by halcyon_diver
ive got a mag 18...its putting out plenty of flow...i think camarojweed was right about it not skimming the surface enough.just need to know how to adjust the water level.
No, I am saying that by increasing the amount of surface flow, you will increase the water level in the tank. It would then cause the water level to rise so the pressure of the increased amount of water over the drain causes it to force more water down it and through the overflow.
However, depending on your system, this might just raise the amount of water in your overflowbox.
Have you cleaned any algae from the teeth of the overflows? Also, where is the drain drawing water from? From the bottom? Or is there a standpipe up top?
 

mikelaubach

New member
If the standpipe is too tall (makes it quieter), you won't have the rush over the teeth that you need to keep the surface scum-free. You may have to shorten the standpipe and allow the water in the overflow to be lower than it is now. Also, don't the AGA's pull from the surface and the midsection somewhere? Try blocking off some or all of the mid-section vents, and it will be forced to draw more from the surface (like a hang-on-back style one does).
 

halcyon_diver

New member
yes. Mike it does draw water at the mid section and the bottom as well, my 120 had the same set up and i didnt have that problem, ill lower the standpipe and see what happens
 

halcyon_diver

New member
well Mike....your the man...i did lower the stand pipe and now the water level in the over flow dropped allowinga much better surface skim...
Thanks a lot...something so simple...
thanks for all the input...certainly appreciated!
 

mikelaubach

New member
Sometimes "luck" beats "good." ;)

Glad it worked out. I had to play with my HOB overflow when I installed a durso in the back. So it wasn't entirely without experience.
 
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