Overskimming

[dsb1829]

I think I have finally acheived a system that is mature and overskimmed. My reasoning goes like this. I have a skimmer that is rated for about a 350g tank. I am running a 72g reef with a 60g sump full of live rock. Total of about 200-250lb of live rock and 130g of water +/-. I have been tinkering with skimmer pumps etc for a while with decent results. About a two months ago I upped my skimming by adding more bubbles to my skimmer via a second becket head. A month ago I swapped to a more powerful pump and a single injector again. In both swaps there was impressive skimmate and good bubble saturation in the mixing chamber. It is so full of micro bubbles that it looks white. After a couple of weeks on the stronger pump, a mak4, the skimmer rarely skims. Bubble saturation is still great, but bubbles won't be rising up the riser to the cup. The cup has been getting very wattery skimmate because of the elevated water levels to get teh bubbles out. So when it is actually skimming it pushes everything out with very wet foam. I have upped my feedings and this has very little effect on keeping the skimmer going. I know that skimmers will basically shut themselves down when water quality is too good. Does this sound like I have the right diagnosis to you?

What is your experience with overskimming? I am starting to figure that I need to have the skimmer off some of the time in order not to starve my tank of the needed plankton. If this is out of your expertise then please let me know who you think could better handle this topic. I figured you may have some insight since you appear to be fairly in tune with current skimmer ideals.

tia...

 

[dsb1829]

Hello.... Is anyone here

Hello.... Is anyone here

Okay, it has been a while. Obviously not too much traffic on this forum. I really don't need to bump the thread, but just want to let you know that I still check it periodically in hopes of a sign of life over here

 

[FMarini]

Hi:
errrrrr. Your right not much traffic here. May I ask what fish is in your tag line?

Okay about your question.
I would not call what your observing overskimming. Overskimming in the general sense is thought to be removal of critcal elements (usually trace elements) from the water which reduced growth of organsims. What your experiencing is sufficient removal of the threshold amount of organics which are minimally required to allow efficient skimming.
First off remember that these skimmer remove organic waste -I will not call it a protien skimmer as there is really not enuf protien in our water to remove to warrent this name. These bubble columns require threshold amounts of organic material in the water which will absorb to bubbles and allow foaming. W/ that said, a reason a skimmer sits idle is becuz you are under that threshold level. Once that threashold is met, foaming will resume.

What this tells me is that your skimmer is sufficient at removing the excess to threshold amount of waste in your tank, and then will not perform anymore.
I do not believe you are starving your tank, if you were you'd be complaining about your corals looking crappy. i don't think your removing too much plankton, as its is unlcear how much micron sized plankton actually gets removed via skimming. My feeling is as you mentioned, leave your skimmer off for a few days, then turn it back on for a few etc, or get a weaker skimmer. Personally i don't think your overskimming.
Does this answer your question
frank

 

[dsb1829]

The fish is an algae blennie. The photo was shot from above with the pumps on, so it is a bit out of focus. However I thought it would make for an interesting signature image. I swap out this image every few months for variety.

I pretty much came to the same conclusion on this. I just worry because we don't know what skimmate is really pulling out yet. Hopefully Dr. Ron can shed some light on that before too long.

I have swapped out to a smaller pump. It still skims quite well and is visibly operational more throughout the day. I am still pulling out a wet skimmate, but would rather go this route than have to clean 1/8" of crud off the skimmer walls to get dark skimmate. Personally I am leaning towards the idea that skimming is removing the same organics wheather you are pulling it out dry or wet. Only real difference is in the quest for dark skimmate you may be remixing some of the organics back in.

If I am reading you correctly you are of the opinion that the skimmer will shut down due to low organic levels before you would encounter the problem of stipping the water of plankton and trace elements. Is this correct?

And yes, you have helped to answer the question. It becomes harder as I advance or digress into reefkeeping to find people who have experience with problems that I have or who also have thoughts on why things work the way they do. It is really nice to have experts such as yourself which we can bounce ideas off.