Nutrient Management by “Old School” Reefer

[Dr. Jim]

I just recently pulled the skimmer from my 20 breeder. I was finally fed up with it stripping my tank. I only put it on because the gas exchange was horrendous on my tank. I did figure out a new trick to replace it though. I use my Apex to have a pump that intentionally pulls air cycle on a regular basis. This keeps the surface clean and also helps some with oxygenation.

Couldn't you just continue using the skimmer to get the oxygenation benefit but let the skimmate drip back into the sump? This is what I am "experimenting" with at the moment.

 

[HuduVudu]

Couldn't you just continue using the skimmer to get the oxygenation benefit but let the skimmate drip back into the sump? This is what I am "experimenting" with at the moment.

The skimmer is killing the things in the cup. For me I want the stuff alive not dead.

My solution for the oxygenation was to run a pump about 10 times a day (technology ftw) that pulls in air. The big benefit of this is that the surface stays clear of scum that impedes gas exchange and gives a short time with increased surface area.

I have come to really dislike skimmers. One upside for them though is in a small tank chemical warfare is real, and skimmers can help with that. For me I think the downsides far outweigh the upsides.

 

[Dr. Jim]

My biggest mistake, other than not using any live rock, had to do with running chaeto. I'd never run macro-algae before and didn't know that it required iron. The chaeto grew well for six months to about the size of a basketball, and then turned light-grey over a few weeks. I didn't know if that was normal for chaeto or not. Figured out it wasn't and that it had died, releasing all the previously-consumed phosphate and nitrate back into my tank. The phosphate bound to my dry rock and left me with about 1 ppm of phosphate. I ended up getting a GFO reactor and using Rowaphos to lower it over several months. I'd guess that single event set me back at least 6-8 months. I only found out about iron by searching for "Chaeto dying" as was not mentioned when searching for "growing macro algae" or "growing chaeto" (which I had done many months before buying anything for my tank).

On another topic, I'm interested in your logic for removing your skimmer. Can you explain?

I'd love to find the secret to growing chaeto with my HOB refugium (with Miracle Mud). I use T.M. Pro salt which is high in iron. I dose iron, and all the elements and my ICP tests repeatedly show adequate levels of everything (except elevated tin). Right now I have some chaeto, caulerpa and ulva starting to turn to mush and am debating having to remove it. I just started dosing ammonia today and stopped carbon dosing hoping that might help and also help my struggling SPS nubs. For the past 2 weeks, every morning I'm finding white tips that need to be snipped. Tons of variables .....considering a thread on this but it would be a long read.

The fact that chaeto won't grow and I haven't had to scrape my glass is suggesting something is inhibiting algae growth which probably includes zooaxanthellae.

 

[Dr. Jim]

The skimmer is killing the things in the cup. For me I want the stuff alive not dead.

My solution for the oxygenation was to run a pump about 10 times a day (technology ftw) that pulls in air. The big benefit of this is that the surface stays clear of scum that impedes gas exchange and gives a short time with increased surface area.

I have come to really dislike skimmers. One upside for them though is in a small tank chemical warfare is real, and skimmers can help with that. For me I think the downsides far outweigh the upsides.

So would you say then that letting the skimmate drip back in may not be beneficial in any way? What about reducing the skimmer DC pump speed to the point where no skimmate is being produced? (I don't want to stop my skimmer completely because it is pulling in outside air very nicely and keeping my pH at 8.2-8.4.)

 

[User1]

The skimmer is killing the things in the cup. For me I want the stuff alive not dead.

My solution for the oxygenation was to run a pump about 10 times a day (technology ftw) that pulls in air. The big benefit of this is that the surface stays clear of scum that impedes gas exchange and gives a short time with increased surface area.

I have come to really dislike skimmers. One upside for them though is in a small tank chemical warfare is real, and skimmers can help with that. For me I think the downsides far outweigh the upsides.

With regards to the air comment from shallow recreational diving perspective. Reef crest, waves, crashing, and the amount of tiny air bubbles. I never worried if my skimmer released micro bubbles for this reason. No skimmer that would be gone. Your comment above makes me wonder if that is a similar effect of mother nature and waves.

The turbulence and micro bubbles. Maybe not a thing. Maybe not important. I have often thought about trying to add a air pump line to one of my gyres and turn it on and off throughout the day when it is in a heavy power/gyre mode.

 

[Subsea]

With regards to the air comment from shallow recreational diving perspective. Reef crest, waves, crashing, and the amount of tiny air bubbles. I never worried if my skimmer released micro bubbles for this reason. No skimmer that would be gone. Your comment above makes me wonder if that is a similar effect of mother nature and waves.

The turbulence and micro bubbles. Maybe not a thing. Maybe not important. I have often thought about trying to add a air pump line to one of my gyres and turn it on and off throughout the day when it is in a heavy power/gyre mode.

You can’t have too much gas exchange in a marine ecosystem like our reef tanks. Divers on reefs with waves report oxygen concentrations > 200% saturation.

 

[Subsea]

So would you say then that letting the skimmate drip back in may not be beneficial in any way? What about reducing the skimmer DC pump speed to the point where no skimmate is being produced? (I don't want to stop my skimmer completely because it is pulling in outside air very nicely and keeping my pH at 8.2-8.4.)

Oxygen is the number one priority. I would suggest running skimmate wet and dump it all back.

 

[Dr. Jim]

Oxygen is the number one priority. I would suggest running skimmate wet and dump it all back.

Yes, I agree about the importance of the oxygenation.... I was just hoping @HuduVudu would clarify what he means by "The skimmer is killing the things in the cup." I think I have an idea but I am wondering about it's significance.

 

[HuduVudu]

So would you say then that letting the skimmate drip back in may not be beneficial in any way?

No, because the dead stuff has nutrients that can be re-used by the tank. To me though that is less beneficial than having live stuff floating around the tank. Let the filter feeders eat the live stuff, instead of remaking more living stuff with dead stuff.

What about reducing the skimmer DC pump speed to the point where no skimmate is being produced?

You're dancing with the devil.

(I don't want to stop my skimmer completely because it is pulling in outside air very nicely and keeping my pH at 8.2-8.4.)

This is legit.

I am not going to tell you the best way to solve the problem because only you can determine based on your needs and your situation what that is. I can say though, before I got my CO2 monitor for the house I would not open the windows for many days at a time. After I got my CO2 monitor I was feeling curious and I decided to go 24 hours without opening the window, thinking that at some point the CO2 would level off. After 18 hours the CO2 was 2400ppm. My house is old (1950s) and I use mini-splits (no air handler). After installing my ERV I don't have to open the windows my house averages 800ppm and ohh yah, my tank keeps a PH of 8.05 to 8.15. Just saying.

 

[HuduVudu]

Yes, I agree about the importance of the oxygenation.... I was just hoping @HuduVudu would clarify what he means by "The skimmer is killing the things in the cup." I think I have an idea but I am wondering about it's significance.

Here is where my thinking comes from ... carbon dosing. Notice how people say that you have to have a skimmer to carbon dose? Why? I asked on another more contentious board how carbon dosing works. After a lot of fights and a bunch of how to answers someone finally linked an article on how it works. Long and short, carbon dosing feeds bugs (for lack of a better word). These bugs are what would cause a bacterial bloom. I have seen these blooms before. The make the water look cloudy with a white color. The skimmer then removes these. The point is that the bloom "bugs" consume phosphate and nitrate and by skimming them out you effectively export phosphates and nitrates. The bugs go into the cup and they die, this is why the skimmate stinks. The cup is effectively anaerobic and these bugs need oxygen to live.

Perhaps you are doing it so that bugs don't die, but I think not.

A quick thought if you are looking for a skimmer without the death why not try a venturi on a pump in your sump. You may get micro bubbles but your won't be killing everything in the water column.

P.S. I am essentially doing this on my 20 breeder.

 

[HuduVudu]

More thoughts in the form of pictures. People think that I am stupid for posting these.

A calm day, but in no way divable. Visiblity would be terribad.

 

[Subsea]

Yes, I agree about the importance of the oxygenation.... I was just hoping @HuduVudu would clarify what he means by "The skimmer is killing the things in the cup." I think I have an idea but I am wondering about it's significance.

Ken Feldman & Sanjay Joshi research paper has detailed a study of bacteria in a reef tank. I have read Feldman’s initial research, but this is a differrent paper with Sanjay Joshi. It might open some eyes on nutrient management in a reef tank.

Bacterial Counts in Reef Aquarium Water: Baseline Values and Modulation by Carbon Dosing, Protein Skimming, and Granular Activated Carbon Filtration

Bacterial Counts in Reef Aquarium Water: Baseline Values and Modulation by Carbon Dosing, Protein Skimming, and Granular Activated Carbon Filtration - What are the bacteria populations in the water column of reef tanks, and how does that value compare with bacterial counts in authentic reef...

reefs.com

[Finally, mechanical filtration in the form of skimming but not GAC does provide an effective means of bacteria export, at least up to a point. It appears likely that some types of bacteria are indeed “skimmable”, but others are not. Thus, skimming inadvertently provides severe (?) evolutionary pressure to skew the tank’s resident water column bacteria population to favor the “non-skimmable” cohort.]

 

[schuby]

Here's my question about running a skimmer: does Sanjay run a skimmer on his big tank that has alot of SPS? I would love to have a tank like his!

 

[Dr. Jim]

Ken Feldman & Sanjay Joshi research paper has detailed a study of bacteria in a reef tank. I have read Feldman’s initial research, but this is a differrent paper with Sanjay Joshi. It might open some eyes on nutrient management in a reef tank.

Bacterial Counts in Reef Aquarium Water: Baseline Values and Modulation by Carbon Dosing, Protein Skimming, and Granular Activated Carbon Filtration

Bacterial Counts in Reef Aquarium Water: Baseline Values and Modulation by Carbon Dosing, Protein Skimming, and Granular Activated Carbon Filtration - What are the bacteria populations in the water column of reef tanks, and how does that value compare with bacterial counts in authentic reef...

reefs.com

[Finally, mechanical filtration in the form of skimming but not GAC does provide an effective means of bacteria export, at least up to a point. It appears likely that some types of bacteria are indeed “skimmable”, but others are not. Thus, skimming inadvertently provides severe (?) evolutionary pressure to skew the tank’s resident water column bacteria population to favor the “non-skimmable” cohort.]

What I found interesting in this article is the idea that protein skimming removes only a certain sub-set of bacteria, the one that happens to have an affinity for bubbles. This could lead to an imbalance of the types of bacteria present (and is suggested as a possible cause of "old tank syndrome.)"

Also of interest, to me, is how recent threads have been offering conflicting "theories" regarding bacteria and carbon dosing. One here in this thread suggests that it is beneficial to maintain bacteria (and even eliminate protein skimming to aid in this process). Perhaps those advocating carbon dosing would fall into this category, at least in part. That part being to increase the population of bacteria to increase the utilization of nitrates. But the conflict would be that protein skimming is needed to remove these bacteria.

Then, we have the idea that carbon dosing can be detrimental (perhaps for more than one reason). If carbon dosing increases the bacterial population then there is more competition for ammoni(a, um) which we would prefer to save for our corals. (@jda explains this better than I).

I'm sure I've oversimplified all this too much, but, both sides make good points. I think I tend to lean toward the idea that it is best to spare the ammonia. But I also am concerned about protein skimming creating an imbalance in the bacterial populations as stated in the article (more than the elimination of the bacteria).

 

[Subsea]

Bacteria are food for corals, sponges and macro algae. Nutrient management uses nutrient recycling to move carbon up the food chain



I see bacteria as the microbial overlords in our reef tank eco systems.

 

[jda]

It has been a decade, or more, but you might be able to find the threads on RC... the bacteria that get skimmed when carbon dosing are mostly already dead and starting to break down which is why they better attach to air to be skimmed. There is a lag from starting dosing or stopping where the bacteria have to die to get fully skimmed out. It is good to factor this into any consideration about if you want to get these out of your tank, or not.

If carbon dosing, I would run a skimmer to get the dead bacteria out of the water column and also as insurance in case a bacteria bloom happens and you can have more of chance of keeping o2 in the water.

 

[Subsea]

I have been using skimmers since 1995 or so. I had the mentality that most do that it is filter/cleaning your water. I had always believed that you needed to do that. Kind of a waste managment type of thinking. Then came live rock (for me 2002). This was well after my three years in the Philippines and what I saw there. It slowly began to sink in for me that the rock was doing the filtering/cleaning, and that I didn't need to do it mechanically. I began to see the protien skimmer as gas exchange only. It was irritating to me to see my diversity slowly die away and I attributed that to the skimmer, right or wrong. During my failed attempt at a salt water aquarium store, I implemented a tank that was a huge success for one and only one thing ... gas exchange. I had never seen anything like it. It was a 175 gallon and plumbed it with an Dolphin Ampmaster and the outputs came from the bottom of the tank. This created a water motion that I believe to be the most conducive to gas exchange. It was amazing. I had a powder blue that had ich and was struggling. I put him in that system, and he cleared up in a few days. At first I didn't make the leap that I no longer needed skimmers. Later though as I thought about what was being stripped out I got it. It is tough if I can't implement a closed system like the one that I had and my 20 breeder is just such a system. I only implemented the skimmer because gas exchange was horrendous and I needed something to help the fish. Now I have found a nice work around, that keeps the surface clear of scum and adds some gas exchange.

I guess I have gone to the hyper-biological thinking. That is kind of why I implemented the digester. I want to do everything through biology. I find biological approaches tend to be really stable and not prone to catastrophe. I still have to use mechanical approaches for some things but if I can remove them and set up a biological approach, I will definitely favor the biological approach.

Kind of long winded but that is how I arrived at a no skimmer approach.

EDIT: My tank eats nitrates so I am not really concerned about a build up of "nutrients" in the tank.

Because this reflects the heart of the thread and of my reef keeping methods, I thought I would quote it.

 

[DaddyFish]

@DaddyFish one of the problems I had when I was doing freshwater tanks was shaking the thinking of doing saltwater tanks. Ultimately I couldn't do it so I stopped. One thinking that does not translate well between fresh and salt is gas exchange. Salt water is VERY difficult to get gases disolved into the water. Fresh water is much easier. Good gas exchange through skimmers and/or large flow (there are other ways) is the hallmark of a successful salt water tank.

It is very hard to remove the filtration mindset. The fear that the tank will be "polluted" is intense. This I think is what causes many people problems in biological systems. It is more important IMO to create a biologically balanced loop than to arbitrarly remove things that the aquarist deems as bad.

I have personally experienced exactly what you describe. I have a 54-gal corner tank that WAS an absolute beast to balance. I kept losing fish, having parasite outbreaks, just could not achieve healthy fish in that tank. Finally I built a wide weir/internal overflow across that dreaded back corner. I added two 12" airstones in the overflow chamber and a good size powerhead to move water in a circular motion around the now pentagon shaped perimeter. It has been night & day better. Tank needs almost zero maintenance, water stays clear with solid parameters, it's truly amazing.

Before the geometry and filtration change that back corner was a dead spot that I could not overcome. It was one day when I was doing some inside painting and opened all the doors and windows of the house that triggered the gas exchange epiphany. Because the next day the pH had magically risen to 8.3, which I could NEVER achieve before, regardless of how much buffer I poured into that tank. The extra oxygen in the room plus the added gas exchange of the airflow over the tank had transformed the water conditions.

 

[DaddyFish]

I experimented a few months with carbon dosing in the form of biopellets. My goal was to remove nitrates.

I also was trying carbon dosing without a skimmer. I was not successful. I did manage to create the correct environment for the nitrate/carbon consuming bacteria to thrive (the proof was in the rapid consumption of the biopellets and a corresponding rapid reduction in nitrates). However, over time of another 4-6 weeks, the nitrates once again skyrocketed. I attribute that to the lack of a skimmer or some other way of removing the "nitrate carrying dead bacteria" from the active water column. So IMO that's why people say you must have a skimmer to do carbon dosing. Without a skimmer the organic matter eventually decays and returns the nitrates right back into the water column.

Once again, nature shows us that the way to get rid of nitrates is to create environments whereby the nitrates are consumed or broken down and eventually released as free nitrogen gas bubbles. Can you say Refugium, Live Rock, Biomedia, slow flow and gas exchange.

 

[DaddyFish]

@HuduVudu I do need to stress this...
I certainly realize that I could reduce the fish population, increase the live rock volume, and leave my tanks alone to let nature find it's balance with great success. What my focus over the past year or so has been, is to find artificial ways to boost the biological load capacity of my tanks without using a large volume of live rock. That goal really doesn't fit into the Trident Method as I understand it, as the Trident requires a given volume of live rock for a given tank size.

My goal is a lot of fish, a little bit of rock, and a muscular filtration system that appropriately compensates for my selfish desires for fish and minimal decor. Good luck, right!!!???