See I told you so!?!?!? Opinions needed.

[Buddyboy]

Hi All,

I've been running my first saltwater tank sumpless for about 3 months now and the constant oil slick problem is ugly and a real pain! Also, the huge AquaC overflow box (works good for bubbles, but not for the slick), the heater, etc. inside the tank takes up too much room and looks fugly as well. Therefore, I must come to the conclusion that... everyone who told me to go with a sump from the start was right!!! Argh! hehe Oh well, the damage is already done...... but I was thinking about going with a CPR overflow box and adding a small sump under the tank. Is it worth it to go this route or should I start again and buy a drilled tank? Starting again would be a real nuisance but the oil slick and lack of space inside the tank sucks. Anyone have any ideas? The tank is 38G (12" wide) so i'm sure I could fit a 10G sump under the tank. Thanks for your thoughts!

Bud

[Samw]

Its not the sump that will fix your surface scum problem. I have a sump and also have a surface scum problem. The reason is because my water return is below the water surface. To fix the surface scum problem, I added an aquaclear 200. The water from the filter is returned above the water line which breaks the water surface and prevents surface scum from forming. You don't really need an aquaclear if you have a powerhead or something set up close to the surface such that it can produce a lot of crashing waves. If you want to set up a sump, you can but you still need to place the water return above the water surface in order to prevent the surface scum from forming.

Having said that, you have an AquaC Remora which should have helped with the surface scum. I guess its because the water that is being returned is going into the prefilter box which prevents the water surface of the rest of the tank from breaking.

[Chaloupa]

We have a 50g with an external overflow as our tank is not drilled and a 13g sump underneath. We still have some surface scum if one of the powerheads has slipped and is not agitating the surface and moving water towards the overflow...we also have the prefilter box on our Remora Pro....yup they take up a ton of space...we were at least able to get the heater out of site...but nothing else. Both of our other tanks are drilled. To do it again we would only go with a drilled tank..they are the way to go but a big pain if you have a set up and want to change it..unless of course you go BIGGER! and just move stuff over! Our water doesn't move overly fast through our sump but if it did we worry about micro bubbles with the sump being so narrow...good luck...you can do it without a sump etc but....

[andrewsk]

I am going to go the other way and say that a sump would help you big time.

IMHO you do not want to break the water surface at all as that will just add annoying bubbles to the water.

First you should have a good strong powerhead close enough to the surface that you can see some serious turbulance in the water. (Not high enough to draw in air though)

Follow that up with an overflow that will pull all of the surface oil/scum into the sump where it is mixed and can be skimmed, etc.

If I had to guess why your skimmer is not working I would think that the input pump might be too far down from the surface to get the crud on top. It should only be an inch or so from the surface. (Just low enough to not draw in any air.

As far as a new tank goes, that is hard. If you can get an inexpensive overflow, then you might be ok. You can always add the Remora to the sump for now. The only problem is redundancy. a drilled tank will have more than one outlet incase one gets plugged.

Good luck and keep us posted!

[Samw]

True about the overflow sucking the scum away. I forgot that my system is set up reversed from the typical setup. My sump is overhead instead of below the tank. So my sump overflows into my main tank. Anyhow, here is the surface of my tank about 10 days after I removed the Aquaclear. Its yucky. But I've repaired the Aquaclear and put it back online tonight. it should clear up the scum in a few days.

[marie]

I have had sumpless tanks since 92 and just set up my first sump 4 mths ago. To get rid of surface scum you need lots of surface action, an aqua clear hang on filter works great and it can double as a fuge. I've never had a problem with bubbles in the water from too much surface agitation, it's always been the skimmer that put bubbles in the water

*Edit* if I didn't have my sump in the basement and had to put up with it under the stand, I wouldn't bother having one at all, it would be a bigger pain in the butt then its worth

[Chaloupa]

I've never had any bubble trouble when using a powerhead to agitate the surface water-we have a maxijet 1200 pointed at the surface right at the top of the tank...only microbubbles from water going through a sump with too few baffles...Samw UGH I'd be putting that AC back on your tank too..my surface scum is minimal~

[Buddyboy]

Well, i've tried using powerheads to break up the surface scum, but I find that all it does is push it to the sides. It's really frustrating! Does a CPR-style overflow box skim water from the surface, or just below the surface?

[reeferaddict]

Originally Posted by Buddyboy

Well, i've tried using powerheads to break up the surface scum, but I find that all it does is push it to the sides. It's really frustrating! Does a CPR-style overflow box skim water from the surface, or just below the surface?

CPR style overflows skim from the surface and will get rid of that... moreso than an AquaClear and certainly to a totally clean level with a couple of powerheads pointed towards the water surface... keeping your surface clear is of the utmost importance with regard to light filtering and gas exchange... Go with the sump... hide the heaters, skim and top off to the sump, and it adds more water volume...

SamW You have a gorgeous tank and I assume that your surface isn't always like that... I will ask what the difference is in DO between scummy and clean... notice any difference?

[Samw]

Originally Posted by reeferaddict

SamW You have a gorgeous tank and I assume that your surface isn't always like that... I will ask what the difference is in DO between scummy and clean... notice any difference?

Thanks. I don't aerate my tank through chopping up the surface of my reef tank. Therefore, the surface scum does not interfere significantly with the aeration in my system. In my system, the aeration is accomplished using an open loop protein skimmer (Currently AquaC Urchin). In the past, before I used this type of skimmer, I had to aerate with a venturi from the Millenium HOB filter. I just measured the DO level in my tank just now with one 150W MH Bulb on and it is 89%. This is the normal level in my tank w/ 1 bulb on at night (w/ no other ambient light). When both lights are on, the DO levels go to about 110%. Without any photosynthesis (lights off), the AquaC Urchin maintains a DO level of 85%. This is an improvement over the venturi which maintained a DO level of 55% with lights off and an improvement over my previous closed loop skimmer which could not maintain a DO level above 35% (probably closer to 20-25%. Didn't wait to find out. I had to turn the venturi back on to avoid killing stuff during this test).