Overskimming?

[2thdeekay]

Thanks hahnmeister. I'd like to see people try the experiment--someone who hasn't dosed ethanol, and has elevated nitrate or phosphate. I don't mean for people to harm their tanks, just test my theory.

I think there are two sides to the equation. Nutrient input on one side, and nutrient export on the other side. Skimming is simply a form of nutrient export, and both sides of the equation should be balanced. This is where the hobby is more an art than a science.

"Can you overskim?" IMHO is not the best question to ask. A better question may be "How do I balance my heavy skimming?" or "How do I balance my high bio-load, or high nutrient import?"

Nice thing about this hobby is that there is more than one way to find that balance!

 

[motopsycho]

<a href=showthread.php?s=&postid=12597715#post12597715 target=_blank>Originally posted</a> by hahnmeister
Overskimming is very real and possible. Using some of the other 'low nutrient' methods with a high-efficiency skimmer can result in no food for your corals. Just by dosing ethanol I killed my chaeto because i dropped my levels too low for it to even grow. So there is that definition... the point where you have removed TOO MUCH.

There is also the definition of overskimming which is simply when the skimmer (often too large for the system) simply runs out of stuff to skim, so the foam head doesnt even form.

I totally agree. My pump on my ER RS-250 stopped working so I was without a pump on my 180G Display (plus 65g sump) for almost 3 weeks. I had planned on doing continuous water changes but I noticed something strange..... the zoa's, hammer, gsp, frogspawn were flourishing. This was about 2 months ago now. I'm now in the routine of only skimming at night and my corals have never looked better. I do feel like I feed heavily as well, feeding 3 times a day various products (NLS, ON1 & ON2, cyclopeze, golden pearls, zooplankton, phytoplankton and a DIY blend I've been using for 2 years) I don't feed all at once and not everyday either

 

[surfjeepzx]

I look at skimming like everything else in the tank... It must all be kept in balance. So my thought is yes, you can over skim and you can under skim. In order to prove my point think about this in an extreme sense. You have a 100 gallon tank with no skimmer and a heavy biolaod = underskmmed.

On the other hand you have a 100 gallon tank with one fish in it and a skimmer designed to handle Shamu's tank at seaworld = overskimmed.

So you see my point.. in a relative sense you can over/under skim.

There's enough experience in the hobby nowadays that you can pretty much get a good idea about the size of skimmer you'll need. Very few people start off with a 300 gallon tank and fully stock it with mature coral colonies, fish, live rock etc. It's a growing process which changes constantly and requires that as it grows, the equipment grows with it if you want to have a healthy and successful tank.

There are also so many variables in this hobby from tank to tank that comparisons are guess work at best. Two identicle tanks with identicle support equipment can vary greatly by differing husbandry techniques which effects the health of the occupants which drives the need for more or less equipment.

For example. my 135 tank and ~10 gallon sump runs great and is heavily stocked. The skimmer I'm using is some old cheapo that I modified for fun with mesh material. Removed the stock venturi and installed a Sedra venturi. That little skimmer couldn't be rated for mor ethan a 75 gallon tank at best in it's original form. It has been running flawlessly for a year now pulling steady skimmate and I have yet to touch/tweak anything.

I have a much larger 30 gallon sump and a G3 waiting to swap in but just don't want to touch the system because it's never looked so good. I attribute the success of the SPS colonies in growth & color to the skimmer not pulling enough skimmate out IMO and the corals are thriving because of it. There are many other variables but I keep adding to the tank in regards to corals and they continue to thrive.

I feel that at some point I will need the larger skimmer as the tank may just outpace the smaller skimmer.

I always read these skimmer threads and get the feeling I'm on one of my car forums listening to the age old, "my engine's bigger than yours". There's much more to the bigger is better theory especially when it comes to aquaria.

 

[jankytomato]

Yep yep, I agree with all points. I'm a no skimmer myself, just don't want it to turn in to something like the deep sand bed thing when someone pulls the plug on their skimmer because it's a trend and crashes their system.

The balance is even more important without the skimmer to pull out excess input without the consequences of it processing in-system.

And thanks for the welcome, glad to see such active discussions! It seems like we're all working towards discovering a more advanced way of doing things. Ecology based is the future, I think, and we need to figure it out and not just try single methods as a magic wand to be disposed of when it doesn't replace all gadgets and stocking limitations.

Related to this discussion: Steve Tyree's cryptic gradient techniques were conceived of as replacement of the skimmer and his systems are no joke, if you've seen any pics.

Deep sand beds, turf algae scrubbers and macroalgae can pull DOC's out of the water column. The only artificial filtration needed in a properly designed ecology based system is some GAC to take yellow out of the water, but that will help combat allelopathy as well so I'd always plan on at least periodically running carbon.

Agreed the danger of taking everything out of the water and the beauty of an eco-system is there's always a little tinge of nitrate and phosphate, but not enough to cause problems. Like my nitrate test is around zero, but the difference between tank water and RODI water tests is the difference between Coors light and MGD. Very hard to tell the difference without tasting it. :rolleye1:

 

[NyReefNoob]

i started a thread about this on another forum site, and really didnt get a answer from this or the other site, overskimming ='s nothing left to skim, i do believe that with skimming you lose x amount of trace element's. i currently have a 50g breeder with a 20g long for sump, it is a sps tank 30 or more piece's, i am using a euroreef rs 135 gatevalve, and mesh mod, i do have 10 fish and feed about 2 cube's of food a day, do switch type's around flake also, also soak selcom 2-3 time's a week and garlic twice a week, more of my concern's was because this is a sps tank that i might pull to much out of the system with a skimmer that's rated for a 100g heavily stcked and having it on a 50g system, i would think that running a much larger skimmer allows you to do a few thing's. have more fish, and feed more, my next system which is a 10g cube i plan on not using a skimmer at all and plan to just fill sump with cheato, but also will only have 2 fish, so i guess i can see the difference, was planning on using a remora urchin pro on main system to see if i notice any difference in corals after a month as well

 

[jankytomato]

Yeah, it would take a few more 20's on some type of habitat gradient system and good flow to replace the skimmer with moderate stocking by most people's standards.

Heavily stocked 50 g would need somewhere around 200 gallons worth of effectively designed crypts and refugiums I believe to function well over the long term. Although even that wouldn't work for a grossly overstocked system.

We have a disgusting pet store locally that has the worst looking fish I have seen besides walmart. Every tank had something dead or dying with sores and lesions, and big giant puffers and groupers in little like 30 or 40 gallon tanks or something like that.

By the time you need that heavy of filtration the fish probably aren't that comfortable and need more space anyway. They might seem fine for a while but the stress will get to them eventually.