importance of nutrient import with ulns's

[RickMartin]

I am glad this message was moved to the reef chemistry forum and not left in the sps forum. Too often well written posts like this are misunderstood and taken for gospel with out a full understanding of the authors system. Scan the posts in the sps forum and people who are having problems get responses almost immediately of "you need to start adding AAs" or some type coral supplement before the water parameters have even checked.

I do have doubts about the carbon dosing actually increasing the export, has any testing been done on the skimmate? I question this because people who stop using it almost immediately start having hair algae and water quality issues. If carbon dosing truly was exporting that much more, there wouldn't be that much nutrients left in the system, would there? You can cook your rock for 2 months and the bacteria will eat all the nutrients in them but you can run carbon dosing for 12 months and when you stop you still have the same problems as before you started. Isn't it possible that the bacteria just ties the nutrients up keeping them unavailable?

 

[Amphiprion]

Isn't it possible that the bacteria just ties the nutrients up keeping them unavailable?

That's actually what is supposed to happen. The said bacteria are then removed via protein skimming, which is the foundation for how this sort of methodology works. In this instance, your protein skimmer is the primary means of export via the removal of whole bacterial cells, which have sequestered N and P.

As for the rebound effect, I'm not sure as to a probable mechanism and can only guess. This is similar to the Marc Weiss products that few people recommended, due to rather vague ingredients (which someone compared to apple juice, I believe). These products, too, eventually had a rebound effect when ceased. I can't say for certain whether or not there were organic carbon ingredients in some of the Marc Weiss products, but it seems plausible, given both the some of the effects, previous analysis, as well as claims on the label of being "organic." Anyway, that's more off-topic conjecture that popped into my head as I was typing. Sorry for the drift.

 

[Randy Holmes-Farley]

disregarding that however since i cant prove it through science, im hoping you can better explain your theory about zeovit using a media surface to bind potassium. what media surface are you referring to?

It is well known that some zeolites, such as clinoptilolite will bind potassium from seawater. Presuming that is what zeovit uses, that is a source of potassium depletion, if not the major one. The potassium gets onto the media surface/pores and binds, just like phosphate binds to GFO. There are many threads on this in the chemistry forum. Here's an article on it:

http://www.drtimsaquatics.com/Library_Presentations/Aquarium_Lit/assets/Clinoptilolite.pdf


it seems that potassium depletion is an issue for many. i have heard and experienced personally that this is due largely in part by needle wheel skimmers, not bacterial growth.

FWIW, I think many people think they have potassium depletion solely because of faulty testing, either by AWT (which seems to have a potassium testing problem of some sort leading to low numbers), or with the KZ kit, which at least in some "bad test kit batches", as I've heard it described, reads low. My Fauna Marin kit so far seems to read my seawater standard OK, for folks who may be interested

Before you posted this, I had actually never heard anyone attribute potassium depletion to a specific type of skimmer, despite reading dozens of discussions of potassium. Potassium by itself CANNOT be skimmed out. If it is skimmed somehow, it must be bound to organics or inorganic particles, or most likely inside of organisms (bacteria, phytoplankton, diatoms, etc).

FWIW, algae like nori is a huge source of potassium for reef tanks (more than most foods relative to the N and P in it), and exported algae will likewise be a big sink. That can be seen in Ron Shimek’s food tests, where the potassium in nori relative to phosphate is much higher than other foods.

http://web.archive.org/web/20010720071031/http://www.animalnetwork.com/fish/data/foods.asp

 

[BradR]

Very interesting post. I also have frustration in managing my little slice of ocean (still gunning for totm some day though ).
There is no question we all have closed systems and it doesn't take much imbalance in the inputs/outputs to really scr*w things up.
It would be great to fully understand what's happening (besides the obvious ca/alk/phos/nitrate levels) and not have to rely on significant maintenance water changes for their stabilizing affect.
That said I believe minimizing inputs of any unknown substances is preferable for system stability until we have a better understanding of what exactly is being consumed/removed.

 

[Canadian]

And for an analysis of skimmate content for those who haven't seen this article check out the following:

http://www.advancedaquarist.com/2010/2/aafeature

 

[RickMartin]

That's actually what is supposed to happen. The said bacteria are then removed via protein skimming, which is the foundation for how this sort of methodology works. In this instance, your protein skimmer is the primary means of export via the removal of whole bacterial cells, which have sequestered N and P.

But wouldn't new bacteria tie up the N and P from the dying bacteria. So instead of exporting it you are just keeping it tied up and basicly skimming off dead bacteria. Actually building up more and more N and P in your tank. If you actually were exporting more efficiently, wouldn't you slowly have to decrease the amount of carbon you added? Until the rock and/or sand had nothing left to release

 

[stanlalee]

But wouldn't new bacteria tie up the N and P from the dying bacteria. So instead of exporting it you are just keeping it tied up and basicly skimming off dead bacteria. Actually building up more and more N and P in your tank. If you actually were exporting more efficiently, wouldn't you slowly have to decrease the amount of carbon you added? Until the rock and/or sand had nothing left to release

who said it was dead bacteria being skimmed? with zeovit live bacteria is said to be shaken from the reactor consumed by corals and well as skimmed from the water column. I've never been given the impression it was dead bacteria (what would be killing it?) Even if what you say happens it still would make it unavailable to algae and out the water column which is the main objective. with non zeovit carbon dosing the carbon dose is backed off after nitrates/phosphates come down (I'm not sure if thats the case or not with zeovit).

honestly I dont care how carbon dosing does whatever it does. all I know is when I do it the glass suddenly never needs cleaning and algae growth of powerhead and such are stalled and when I stop immediately the glass, powerheads and such require more maintenence. when I begin again it goes back to staying clean. I dont care about all the color manipulation and whatever else zeovit is suppose to do (want pretty corals, buy pretty corals and keep them happy lol).

 

[Amphiprion]

It is reasonable to assume a combination of both living and dead bacterial cells are removed via protein skimming. However, what sort of ratio of the two likely varies considerably based on any number of factors.

 

[dieselgrk]

FWIW, I like to change my water 1% daily. I use Instant Ocean for that.

thank you randy for the links in response to my previous post; very interesting reads.

as for salt, why is instant ocean your salt of choice?

 

[Randy Holmes-Farley]

:thumbsup:

Here’s a cut and paste from another thread of why I elect IO:

I do not think there is a "best" salt mix. Nearly all of them will work fine as long as you know their pros and cons.

I don't want excessive borate, which leaves out Seachem.

I don't want vitamins or anything else organic in my mix (because I doubt their utility, they degrade with time to who knows what, bacteria may thrive on them as I store new salt water for a substantial period, they are totally undescribed with respect to amounts or identity, they are not naturally present in natural seawater at appreciable levels, and because I've occasionally had them mess with my skimmer), so that tosses out some like Reef Crystals, hW Marinemix Plus BioElements, Kent, Coralife, and Nutri-SeaWater.

I don't want excessive calcium (long term use of limewater as I use drives up calcium, so I do not want it starting high), so that tosses out a bunch, such as Kent, Seachem, Coralife and Oceanic.

There are certain companies that I will not support due to their misleading claims and/or product lines. That tosses out a few which I won't detail here since it is my personal thought as opposed to a specific issue with their salt mix.

I won't use certain lines of natural seawater due to excessive metals in it.

That only leaves a few to choose from, such as Instant Ocean and Tropic Marin Pro. The remaining ones might all be fine for me, but IO is lower in cost, especially if you get it when it goes on sale (which it frequently does). It also has a very long track record of success in many aquaria with relatively few concerning issues of bad batches.

 

[dieselgrk]

thanks randy.

how about your carbon dosing: what organic carbon do you dose? how much do you dose? and what effect dose organic carbon dosing have on your system?

the zeovit guide offers this brief explanation as to what the organic carbons purpose is:
"This product [organic carbon] is a liquid food source and promotes the reproduction of all nitrifying bacteria in the aquarium. It is therefore very effective in reducing phosphate (PO4) and nitrate (NO3.)"
-bacteria food (zeostart 2), Zeovit Guide, 1.03, pg. 12

would you agree with this statement?

 

[Randy Holmes-Farley]

Well, I'm not sure of their basis of thinking organic carbon dosing has much to do with nitrifying bacteria (those that convert ammonia and nitrite into nitrate), but organic carbon dosing does drive bacterial growth and can help reduce nutrients. The bacteria can be exported with a skimmer or manually (like when I clean them off of my GAC) or can help feed tank organisms that are able to feed on them.

Some organic carbon sources (such as acetate from vinegar) can also be used directly by corals and such.

At the moment, I dose mostly vinegar and some vodka to my 120 gallon display (maybe 200-250 gallons total volume). About 270 mL of vinegar and 5-10 mL of vodka spread through the daylight hours. I saturate the mix with calcium hydroxide to offset any pH drop from the vinegar and the CO2 produced.

I am using it as one of several nutrient export techniques (lit refugia, skimming, large amounts of live rock, etc). I started in an effort to reduce the expense of the lit refugia I had, and in that sense it has been successful, although I still have 525 watts of lit refugia (8-12 h/day).

If I stop organic carbon dosing for a day or two, algae grows faster on the glass. Some soft corals seem to be growing a lot faster with the dosing. Aside from that, I've not noticed any differences. No color changes in anything (and I was not hoping for them).

 

[Shadowramy]

Randy,

You talked about the clinoptilolite zeolite binding potassium, why would someone choose this zeolite? Does it have a benefit?

** Just read the article, "commonly used material for removing ammonia from aquarium water"

Zeovit claimes they use "several' zeolites, any idea of what some of the others migth be?

Thanks Randy

 

[Randy Holmes-Farley]

No, I don't know what they are, or if they are even different ones as opposed to different types or forms or shapes/sizes of clinoptilolite. They do not say, although clinoptilolite is widely discussed in the zeovit context, even on their web site about "natural" zeolites.


Some folks have suggested that ammonia binding is an important aspect of the zeolite for getting good bacterial growth, but I don't believe it. We discuss that here:

http://www.reefcentral.com/forums/showthread.php?t=1783421

 

[dieselgrk]

Well, I'm not sure of their basis of thinking organic carbon dosing has much to do with nitrifying bacteria (those that convert ammonia and nitrite into nitrate), but organic carbon dosing does drive bacterial growth and can help reduce nutrients. The bacteria can be exported with a skimmer or manually (like when I clean them off of my GAC) or can help feed tank organisms that are able to feed on them.

the carbon source (ZEOstart2) is in place to feed the bacteria (ZEObak) which is added to the system as part of the 'basic 4'.

this information is offered in the zeovit guide as an explanation as to what the bacteria is doing:

"The added microorganisms work in principle as a chain reaction, which reduces substances step by step until the skimmer is able to permanently remove it from the tank."
-Microorganism solution (ZEObac), Zeovit Guide, 1.03, pg. 8

if you were to take into consideration the above statement extracted from the zeovit guide and combine that with the statement i posted previously, which is also extracted from the zeovit guide:

"This product [organic carbon] is a liquid food source and promotes the reproduction of all nitrifying bacteria in the aquarium. It is therefore very effective in reducing phosphate (PO4) and nitrate (NO3.)"
-bacteria food (zeostart 2), Zeovit Guide, 1.03, pg. 12

then to it sounds very similar to what you are explaining:

"organic carbon dosing does drive bacterial growth and can help reduce nutrients. The bacteria can be exported with a skimmer or manually"
-Randy Holmes-Farley

i do have a few questions/remarks about the link you posted regarding clinoptilolite zeolites.

is Clinoptilolite just one type of zeolite.and if so are there many different types of zeolites which do (absorb) many different things?

as for the article, not only does it focus on one type of zeolite from my understanding. it also is quite self contradicting. Dr. Timothy A. Hovanec states that,

"As more salt is added to the water, the sodium concentration becomes much greater than the ammonia concentration and the sodium ion is adsorbed over ammonia. It doesn't take much salt to have such an effect. Studies have shown that a salinity of 5 ppt (seawater, for comparison, is about 33 ppt) will decrease the ammonia adsorption capacity of clino 10 times. As the salt concentration approaches that of seawater, less and less ammonia is removed by the clino."

i interpret this as saying, clinoptilolites are absolutely worthless in salt water! but then Dr. Timothy A. Hovanec goes on to say,

"...clinoptilolite should not be counted on as the major ammonia remover in the aquarium filtration system. It is too inefficient and slow to keep up with the ammonia production in an average fish tank. Instead, use it for emergency or special situations."

i interpret this as saying, well they work, just not that well. but when you really need them in an emergency, they work.

it is stated in the zeovit guide that three different types of zeolites are used in their mix. perhaps clinoptilolites make up one of the three kinds, perhaps clinoptilolites are not used at all. at any rate, zeolites are just one part of the whole system.

 

[Shadowramy]

I know zeovit says these can not be "re-charged", but according to the paper these can be;

"The re-charging process is usually done with a brine solution of sodium chloride. A solution of 20 g NaCl per liter adjusted to a pH of 12 is prepared. This solution should be recirculated through the clino for a total of 150 to 200 bed volumes (one bed volume equals the volume of the clinoptilolite). The clino should then be rinsed with very soft water (deionized or reverse osmosis water is best) for several hours before being used again in the aquarium filtration system."

This sounds like a pretty simple process if you have a bucketfull of old zeolites, I am wondering why zeovit is saying they can't be re-charged?

Also the articles also advises against using in saltwater, basically saying they would preform very poorly. However I can tell when the zeolites have expired in my system, my corals start to loose some color and get a 'washed out' look to them, so at some level they must work or am I seeing something else take place?

Is there a better zeolite that can be choosen?

*** okay I just skimmed over some of the thread Randy refered to then it hit me, wouldn't just taking a bunch of live rock rubble (of different sizes) and chucking them in a zeoreactor not only do a better job but would also last much longer?



thanks

 

[Randy Holmes-Farley]

I don't think Tim contradicted himself. Clinoptilolite binds far less ammonia in seawater than in fresh water. But it can still bind some and may still be useful if the goal is to bind ammonia with a solid media.

is Clinoptilolite just one type of zeolite.and if so are there many different types of zeolites which do (absorb) many different things?

There are many yes, but most are not known to do anything useful for reefers in seawater. The huge amount of salt present makes for fierce competition for any binding sites. Clinoptilolite binding some ammonia is among the very few (maybe the only one) known to be useful in seawater by binding something.

it is stated in the zeovit guide that three different types of zeolites are used in their mix. perhaps clinoptilolites make up one of the three kinds, perhaps clinoptilolites are not used at all. at any rate, zeolites are just one part of the whole system.

Quite true.

 

[Randy Holmes-Farley]

However I can tell when the zeolites have expired in my system, my corals start to loose some color and get a 'washed out' look to them, so at some level they must work or am I seeing something else take place?

I do not know what that effect is from, but one possibility is that the zeolites are coated with bacteria and do not as well support further growth. Tim's article doesn't address biological fouling of zeolites, but it certainly happens to most any media added to a reef tank, including GAC.

 

[Reefer08]

At the moment, I dose mostly vinegar and some vodka to my 120 gallon display (maybe 200-250 gallons total volume). About 270 mL of vinegar and 5-10 mL of vodka spread through the daylight hours. I saturate the mix with calcium hydroxide to offset any pH drop from the vinegar and the CO2 produced.

Wow 270mL of vinegar! Could you explain the calcium hydroxide that you saturate your vinegar with? How much do you add to the vinegar and what are the ratios? Is the purpose only to raise the vinegars pH? What pH does vinegar have naturally? Thanks for the advice

 

[Reefer08]

Randy how about dosing acetic acid in our reef tanks rather than vinegar? It would be easier to dose a few drops of it rather than a large amount of vinegar. Im wondering if zeofood7 is actually acetic acid because it smells exactly like vinegar and also claims to be food for the corals.