Does an ATS remove DOC

[Floyd R Turbo]

Now add this to what they are saying.

30-40% of bacteria is skimmable, meaning it has the correct hydrophilic properties required to be removed via bubble fraction. Here is the big white elephant in the room, there are both good and bad types of bacteria, a good reef tank always wants to have the majority of the bacteria to be the good type. If you can sustain a greater ratio of good to bad bacteria, the natural population cycles of the bacteria will keep each other in check, the majority will always reproduce more to sustain a majority balance. How do we know that the 30-40% of the bacteria being skimmed is not the good type and you are then skewing the ratio in favor of the bad type to multiply in the tank and wreak havoc.

The answer is, we don't know. So if we don't actually know if we are helping or harming our tank by removing stuff via skimming, then why do it? Why not let the tank find its own natural balance instead, it will make the entire reef tank keeping experience much more peaceful and stable overall. Sure, there are certain scenarios where a skimmer can help, like an accidental extreme overfeeding, but if that happened it would actually be cheaper to do a 100% water change to fix that issue than it is to buy a skimmer for those super rare occasions.

+1 to that. I started thinking that the second I read that article. Totally sold me against skimmers.

[leebee]

Let me just say this, I am all for going skimmer less. I did it years ago, and I would do it again. I will be building a scrubber as soon as all the parts turn up in the post. The only problem I am seeing now is what happens to all this bacterial plankton after it dies off, does it just settle to the bottom to be consumed by something else, does it release nutrient back into the water column. The basis of carbon dosing is to skim bacteria out after they have done their job, therefor removing N&P. I am worried that this is not happening with an ATS and no skimmer. Maybe SM can add his knowledge on this subject. I know this system works great, and I’m not questioning the effectiveness of an ATS, I just want to get it all worked out.

[Floyd R Turbo]

Even the detritus that everyone is so anal about trapping with filter socks and siphoning out of the sump and blowing off the rock can be left alone

http://algaescrubber.net/forums/show...light=detritus

I'm sure the plankton you are talking about falls higher on the chain than this stuff. I wouldn't worry - AT ALL

[Ace25]

I know Santa Monica has some good info for leebee on the subject.

In the mean time, I thought this was a rather neat little learning tool.

http://coolclassroom.org/micro_test/...ons/ML/ml.html

[SantaMonica]

what happens to all this bacterial plankton after it dies off

It is eaten by microbes even before it dies. Just like in the ocean, where there is no skimmer.

[leebee]

Sorry to go on about this, but I’m still not sure. A fish tank is a closed ecosystem that we add food to year after year. With no water changes and no means of nutrient export, this has to build up somewhere. It might be at a microbial level, or in the animals and algae that inhabit our tanks. A certain amount of nitrate will convert to free nitrogen through anaerobic bacterial action, and phosphate will absorb into the rocks and sand. The use of an ATS(or a macro refugium, carbon dosing) will be the only way I can see of exporting N&P, as this is something actually being removed. If you are putting food in at one end, something has to remove it at the other, it can’t just keep building up.

Of cause, comparing our little glass boxes to the oceans of the world is a very huge stretch, but they are part of a closed system also, the Earth. Every element on Earth is just re cycled, nothing new is added, the Iron in your steak probably welled out of the ground a billion years ago, and passed through many animals before it got to your plate.

As I stated before, I am an ATS believer, every tank should have one, but I think more is going on than what meets the eye.

[Ace25]

In my opinion, this is where the balance thing comes in. If you can find and maintain the balance of the microbial loop then everything works as it should and gets recycled or removed. For someone like me who feeds on the heavy side, I feel I tend to form a buildup in the DOC/DOM level of the cycle. I don't have enough bacteria to handle the job as quickly as I would like and eventually I see issues I feel are related to a DOC buildup. This is also fairly normal under aquarium conditions. We normally only have a fraction of the amount of bacteria per volume of water as the ocean does, but this can vary greatly from tank to tank, some can have near NSW levels but it is rare.

This is why I use purigen to reduce the DOC levels in my tank to get back to the balance where bacteria can then handle the rest. Easy solution for me I know, stop feeding so much, but I like fat happy fish and I can't help it. Since every tank is different and every person has different habits so it comes down to understanding what issues to look for and how to correct them in order to keep the cycle balanced and working efficiently.

[SantaMonica]

nutrient export, this has to build up somewhere

Food in = algae out.

We normally only have a fraction of the amount of bacteria per volume of water as the ocean does

Aquariums normally have about the same number of bacteria per unit volume as ocean water. What you don't have, is sediment subduction, and therefore unless metals are removed from aquariums by algae or other means, metals will accumulate.

[Ace25]

Aquariums normally have about the same number of bacteria per unit volume as ocean water. What you don't have, is sediment subduction, and therefore unless metals are removed from aquariums by algae or other means, metals will accumulate.

This article seems to counter your statement. Look at Table 1. Bacterial counts from authentic marine water, various control samples, and several reef tanks. http://www.advancedaquarist.com/2011/3/aafeature Oddly though, all the tanks that had a fraction of the bacteria of NSW all had sandbeds, and the ones that were closer to NSW did not.

[SantaMonica]

Yes I've seen that, but I was going off of marine biology studies I've read in the past. More numbers that I should have saved.