Protein Skimmers Works better in the night?

[danielfernandes]

I'm using a HOB skimmer here. I noticed that during the day the bubbles are in the middle of the neck of the glass without removing any impurity. However, during the night, the bubbles turn into foam and overflow a little into the glass, apparently fulfilling their function.

My question is: Is there any reason why the skimmer performance improves overnight? What causes this change? Is it ok to just put off in the night?
Thanks.

 

[Dan_P]

I'm using a HOB skimmer here. I noticed that during the day the bubbles are in the middle of the neck of the glass without removing any impurity. However, during the night, the bubbles turn into foam and overflow a little into the glass, apparently fulfilling their function.

My question is: Is there any reason why the skimmer performance improves overnight? What causes this change? Is it ok to just put off in the night?
Thanks.

Certain molecules in the aquarium water that collect on the bubbles strengthen them, preventing their collapse. In turn the surviving bubbles accumulate and create a foam that rises up and out of the skimmer. These molecules vary in amounts. I have the same pattern in my system and raise the top of the foam head so it is at the top of the tube and I collect skimmate around the clock.

Here is a thought. If you aren’t collecting skimmate, you are not removing waste. Some waste does not form very stable bubbles and unless you raise the foam level, this waste is not removed. This is what is known as wet skimming. Because many aquarist employ automatic top off water systems, they cannot wet skim without diluting the salinity in their system. This means organic waste is not removed as well by skimming. I have no idea if this is good, bad or who cares. I do it because I want my creatures living in water that resembles the low dissolved organic carbon of their natural habitat.

 

[danielfernandes]

What I don't understand is why foams form more easily at night. Just with the change from day to night, before I even feed the fish.

 

[davidcalgary29]

Lower nighttime tank temperatures? Variations in SG from ATO operation? This is an interesting read.

 

[trevorhiller]

I have no idea on this one. I’ve never heard of skimmer fluctuations between night and day.

Perhaps it is because you are feeding during the day and the food is being broken down throughout the day so by the time night comes around there is more organic matter dissolved in the water to allow the skimmer to work better?

Like I said, I have no idea…just a hypothesis

 

[Waters]

If I had to guess, it is due to the water being left alone for hours, which allows the skimmer to "settle down" and start producing. Throughout the day as you feed and mess around with the tank, it irritates the skimmer.

 

[Mr. Mojo Rising]

This is what I think:
Food intake and photosythesis happen during the day. At night the creatures rest and expel the waste, the article below explains that so much waste is expelled at night that ph drops at night (which we all know). Since more waste being expelled at night it makes sense the skimmer will perform better at night.

http://reefkeeping.com/issues/2003-06/rs/feature/index.php

 

[GMay]

pH is higher. Foam fractionation (skimming) works better at higher pH and higher salt. These are reasons you do not see skimmers used in freshwater aquaria.

 

[Eric Cohen]

Not sure if anyone has mentioned this, but I have had this experience before too and found out that the energy coming from the city surges at night when the demand is low, so your pumps are actually getting more power which causes the skimmers to work differently. The solution could be, 1. Lower the skimmer at night (PITA), 2. Get a power regulator, 3. Call your municipality and talk to them to see what they say...maybe they can adjust the power? And good luck on that! lol. We actually use to lower the skimmers a bit every day, but Im talking commercial situations.

 

[JoeinLA]

Interestingly I’m having the same day/night performance experience and came across this thread while looking for an answer. not sure if there’s an action to be taken here but seems like the comment above re waste being expelled at night seems like a reasonable cause?

if I turn up my skimmer for the day, then my skimmate is too wet and my ATO gets triggered. I have to counter this by lowering my pump performance over time between water changes when I can re-level the water line in the tank.

was thinking of maybe playing with air mix, but my skimmer doesn’t have an air valve built in so I’ll try adding one.

 

[TeeJay87]

pH is higher. Foam fractionation (skimming) works better at higher pH and higher salt. These are reasons you do not see skimmers used in freshwater aquaria.

pH is higher during the day (when his skimmer is not skimming) and pH is lower at night (when his skimmer is skimming), so your comment can’t be the explanation.