refugiums

Still reading... found the final report, also on the NOAA site. Holmes-Farley mentions adsoption and desorption of phosphate on aragonite in his article as well.
 
<a href=showthread.php?s=&postid=11356046#post11356046 target=_blank>Originally posted</a> by gwaco
try this

http://209.85.165.104/search?q=cach...s+leaching+phosphate&hl=en&ct=clnk&cd=3&gl=us

wow. I love palms and spend a regular amount of time on the UFL website as they have great horticulture resources. One thing I CAN tell you is that this article applies to commercial, container-grown plants. Plants that grow in saline soils (ie Cocos nucifera) react totally differently than those that have low tolerance to high levels of dissolved salts.

If that isn't enough, the purpose of this article is to discuss the effects of fertilizers on the environment, and how controlled-release fertilizers can decrease the "leaching." The dynamics will be totally different in a mangrove, which has a submerged root system, a completely different medium (substrate), and higher tolerance for dissolved salts (similar to high levels of fertilizers in potted plants).

Basically, this article has no relevance to our discussion. It appears that you googled it and pasted it without really taking the time to find out what it was about.
 
<a href=showthread.php?s=&postid=11353391#post11353391 target=_blank>Originally posted</a> by triggerfish1976
Both.
Did you get a chance to read this entire thread about the nutrient absorbtion properties of marine plants or lack there of?

Lack thereof? If you're talking about plants (like a mangrove or palm), they definitely use nutrients. If you're speaking of algae, check the article by holmes-farley for a link to the percent phosphorus and nitrogen by dry weight of Caulerpa sp. algae.

Yes, it's true from the articles that have been posted that nutrients are leached by plants. However, those same articles show how small a percentage is actually leached. Additionally, they suggest that leaching occurs in the absence of DOCs (i.e. a nutrient-free tank). The article here http://www.aoml.noaa.gov/ocd/sferpm/millero/mil
clearly states that phosphate is a limiting nutrient in pest algae growth. So, the logical consequence of that would be that algae USES phosphate in it's biological processes.
 
I agree with cobra and maintain my original position. In many of those articles, even though most of them have nothing to do with marine plant nutrient absorption, it speaks of nutrient recycling which is important in any environment.

I do not run a refugium but I have a ball of chaeto in my sump. Everytime I trim it back, I always seem to have an algae breakout on my sandbed.
 
<a href=showthread.php?s=&postid=11449834#post11449834 target=_blank>Originally posted</a> by flasher1

I do not run a refugium but I have a ball of chaeto in my sump. Every time I trim it back, I always seem to have an algae breakout on my sandbed.

I think both of you are still missing the bigger picture that is trying to be relayed here. If just trimming a "small" ball of Chaeto is causing a cyanobacteria outbreak then there are other underlying issues going on in the tank. You seem to be operating on a very tight rope and that seems to be the general problem when running refugium type setups as a main or secondary form of filtration. Based on the the data provided thus far and personal experience the best form of biological filtration is not having to rely on it at all. This is accomplished by removing nutrients before they are allowed to start breaking down in a tank. This is accomplished by having high flow, bare bottom tanks, elevated rockwork, efficient mechanical filtration in the form of filter socks or pads, and a efficient skimmer.
With that being said, this creates a pretty sterile looking tank that many hobbyists just don't find aesthetically pleasing since they still want the total "reef tank" experience that includes inverts (snails, hermits, starfish, urchins, etc) and sand. A committed hobbyist can still have a successful reef tank with all forms of coral but they are certain maintenance regiments that generally must be followed in order to do so. This includes stirring or replacing the entire sandbed on a regular basis, keeping a "huge" refugium (generally a tank equal in size to the main display - Randy Holmes Farley even mentions this in his articles) and constant pruning in order to remove all of the phosphates that the plants have stored before they have a chance to leech back into the tank. Unfortunately the average hobbyist fails to make this sort of commitment and within a couple of years the tanks generally experience some sort of crash due to a PO4 meltdown so to speak.
One thing I have learned in this hobby is to just use scientific research as a starting point but not to let it define my decisions regarding how to keep my tank. Considering that most of the data is based on natural reef environments or limited confined lab experiments by scientists with specific agendas.
 
You should try a fuge. They are soooo easy. rDSB takes zero upkeep and cheato takes almost none, weekly trimmings, up to a month is ok. Much easier than high flow and keeping the bare bottom clean.
 
i did have a fuge,now it has been offline for 2 weeks with NO major changes in phos or nitrates,also NO algae blooms of any sort.i dont believe that most refuges people have are large enough or maintained properly to be of any real benefit to the system.also what is hard about high flow and keeping the bottom clean?the flow keeps it clean,nothing hard about that.
 
<a href=showthread.php?s=&postid=11451300#post11451300 target=_blank>Originally posted</a> by ls7corvete
You should try a fuge. They are soooo easy. rDSB takes zero upkeep and cheato takes almost none, weekly trimmings, up to a month is ok. Much easier than high flow and keeping the bare bottom clean.

Trust me I have tried refugiums and there is more maintenance than that. You are basically having to keep two tanks in order to try and maintain one. Sounds like fuzzy math to me.:D
The reason why high flow is needed in BB tanks is so the detritus and other waste products never even see the bottom of the tank and are pushed into the overflow and immediately removed by filter socks or pads. The only maintence involved is changing out the filter as apposed to stirring the sand, trimming algae (should be done daily if the refugium is the correct size and working properly), changing bulbs, and cleaning the tank.
Honestly, I am not knocking people who keep DSB's or refugiums. If it works for you then great. All I am trying to say is there is a massive amount of misinformation out there about there efficiency as a filtration method but obviously my opinion is only my opinion.
 
I have pretty much kept most macro algaes available to hobbyists but the mains one were:

Chaeto
Various Caulerpa
Maidens Hair (Chlorodesmis)
 
You still have these issues with chaeto as apposed to caulerpa? The sand bed will do nothing if it is always disturbed.

Added volume is a bonus, not a downside.

I dont think misinformation is the probelm, possible poor execution but the hobby has evolved to the point setting up a fuge is almost trivial.
 
<a href=showthread.php?s=&postid=11451173#post11451173 target=_blank>Originally posted</a> by triggerfish1976
I think both of you are still missing the bigger picture that is trying to be relayed here. If just trimming a "small" ball of Chaeto is causing a cyanobacteria outbreak then there are other underlying issues going on in the tank. You seem to be operating on a very tight rope and that seems to be the general problem when running refugium type setups as a main or secondary form of filtration. Based on the the data provided thus far and personal experience the best form of biological filtration is not having to rely on it at all. This is accomplished by removing nutrients before they are allowed to start breaking down in a tank. This is accomplished by having high flow, bare bottom tanks, elevated rockwork, efficient mechanical filtration in the form of filter socks or pads, and a efficient skimmer.
With that being said, this creates a pretty sterile looking tank that many hobbyists just don't find aesthetically pleasing since they still want the total "reef tank" experience that includes inverts (snails, hermits, starfish, urchins, etc) and sand. A committed hobbyist can still have a successful reef tank with all forms of coral but they are certain maintenance regiments that generally must be followed in order to do so. This includes stirring or replacing the entire sandbed on a regular basis, keeping a "huge" refugium (generally a tank equal in size to the main display - Randy Holmes Farley even mentions this in his articles) and constant pruning in order to remove all of the phosphates that the plants have stored before they have a chance to leech back into the tank. Unfortunately the average hobbyist fails to make this sort of commitment and within a couple of years the tanks generally experience some sort of crash due to a PO4 meltdown so to speak.
One thing I have learned in this hobby is to just use scientific research as a starting point but not to let it define my decisions regarding how to keep my tank. Considering that most of the data is based on natural reef environments or limited confined lab experiments by scientists with specific agendas.

I actually agree with most of what you're saying here. My argument was only against the ideas introduced that seemed to suggest that macro/mangroves don't absorb nutrients. Another thing to remember is that while skimming is effective at removing organic compounds, it does little in the way of removing inorganic compounds (such as orthophosphate). Since orthophosphate is a limiting nutrient only at levels below 0.03 ppm, relying on something to get all the organic compounds before they break down is a little idealistic.

One thing I wasn't really aware of was the desorption of phosphate from aragonite. I'm definitely going to need to check in to this more as it could become a major problem in the future. Although I doubt elevated phosphate levels from leaching could alone cause a tank crash, it's still an important consideration. Thanks guys for bringing this to my attention.

As for manually "stirring" the sand bed, I have to ask why this is necessary. Both macro and micro fauna in a sandbed should basically make this a non-issue. Is this an incorrect assumption? (we all know what happens when we assume...)
 
Anyone have and graphs/data showing the reduction of phos caused by dosing nitrogen to increase macro growth? I have heard good things about this technique but havent seen any data on it.
 
<a href=showthread.php?s=&postid=11451533#post11451533 target=_blank>Originally posted</a> by cobra2326
I actually agree with most of what you're saying here. My argument was only against the ideas introduced that seemed to suggest that macro/mangroves don't absorb nutrients. Another thing to remember is that while skimming is effective at removing organic compounds, it does little in the way of removing inorganic compounds (such as orthophosphate). Since orthophosphate is a limiting nutrient only at levels below 0.03 ppm, relying on something to get all the organic compounds before they break down is a little idealistic.

As for manually "stirring" the sand bed, I have to ask why this is necessary. Both macro and micro fauna in a sandbed should basically make this a non-issue. Is this an incorrect assumption? (we all know what happens when we assume...)

Regardless of what all of these scientific reports say, do you honestly think that it is more efficient to allow nutrients (food and waste) to stay in the tank long enough to break down so it can be consumed by bacteria and algae all the while releasing organic/inorganic phosphates and ammonia into the tank. You would be surprised how much nutrients certain foods actually add each time you feed them. Each time you feed it just keeps compounding.
I don't know about you but I would rather just get it out before it even has a chance to do this and that is why I believe in the BB/high flow method over the fuge/clean up crew method.
My philosophy is if you have enough nutrients in the tank to sustain macro algae then you have a nutrient problem.
When I say problem I mean PO4 levels that inhibit calcification and color in SPS corals.
Don't get me wrong, I have seen beautiful tanks with fuges but we are after all talking about the next level of SPS coral husbandry here so if you are mainly looking at keeping soft coral and LPS then all of this really isn't an issue as long as you follow good husbandry techniques.
 
<a href=showthread.php?s=&postid=11452535#post11452535 target=_blank>Originally posted</a> by triggerfish1976
Regardless of what all of these scientific reports say, do you honestly think that it is more efficient to allow nutrients (food and waste) to stay in the tank long enough to break down so it can be consumed by bacteria and algae all the while releasing organic/inorganic phosphates and ammonia into the tank. You would be surprised how much nutrients certain foods actually add each time you feed them. Each time you feed it just keeps compounding.
I don't know about you but I would rather just get it out before it even has a chance to do this and that is why I believe in the BB/high flow method over the fuge/clean up crew method.
My philosophy is if you have enough nutrients in the tank to sustain macro algae then you have a nutrient problem.
When I say problem I mean PO4 levels that inhibit calcification and color in SPS corals.
Don't get me wrong, I have seen beautiful tanks with fuges but we are after all talking about the next level of SPS coral husbandry here so if you are mainly looking at keeping soft coral and LPS then all of this really isn't an issue as long as you follow good husbandry techniques.

I agree. However, since I already have a sand bed, and I do believe that there are some benefits to having one, my approach will probably be to do both. Remove as much organic material from the tank by way of skimming and mechanical filtering, and let the sand bed and clean up crew pick up what was missed. My point was only that no matter how good your filtering is, you're going to miss something. Again, considering how low phosphate levels must be to become limiting, it's a good idea to have a back up plan. Conversely, simply leaving detritus and other organic matter to decay is very poor practice. It would be silly to think that all the DIPs would be consumed by the macro in the fuge and not be consumed by algae in the tank.

To a point, I suppose the live rock in a BB tank can pick up this slack. Perhaps other phosphate binders could also be used.
 
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by the logic of some of these comments, a dry tank would be the ultimate method for phosphate control.

because you know, if you put nothing in, no need to take anything out.

life is life. water will carry everything with it. if someone found a method to sustain the nasties in a controllable growing algae, so be it. What's the difference between that and your phosphate reactors. you eventually have to replace media...

minus well work for the companies that tell everyone their methods of such and such are better. i dont know though, millions of years of evolution in the ocean doesn't hold a candle to a phosphate reactor though...
 
The zooxanthellae need the same nutrients that the macro needs. A fuge can keep nutrient levels are very very miniscule amounts. I feel that you have had a bad experience with them in the past and are letting that experience steer new comers to the hobby away from the cheapest and easiest way to control excess nutrients.

By the same logic as loosbrew was commenting on, if the nutrients put in to the tank are that terrible then a planted FW tank or even lagoon/seagrass tank that is dosed with NPK must be a disaster, but of coarse they are not.

triggerfish1976 should setup a fuge and challenge this himself. even on 600g it would be childsplay to setup.
 
<a href=showthread.php?s=&postid=11353786#post11353786 target=_blank>Originally posted</a> by The Hawk'ster
After reading this post of its entirety (including articles) and having lunch with gwaco I have decided to take my refugium off line (refugium running for 3yrs / main tank is 9yrs+ running) Tank Crashed overnight...thanks gwaco JK :D

Anyways my No3 is running at 26.6ppm and PO4 is .02 maybe less
I will keep you updated.

UPDATE:

It has now been a little over 2 weeks since the refugium has been offline. The 1st week No3 and PO4 had no change. I had the PO4 tested on a hanna meter and the reading was .16 2nd week PO4 is maintaining @ .02 or less and No3 went up to 36 plus. The only thing different that I have done is I started straining food and rinsing with R/O water before I feed and I cranked the skimmer up so it skims wet.

I was having a slight cyno problem and since the refugium has been offline it is completely gone. Now I do not know if it is because I cranked the skimmer up, took the fug offline, straining the food or all off the above. It also can just be a coincidence.

Now for my nitrate problem. Since my nitrates went up + 10 and my PO4 has not gone up or down I can only assume that the refugium was helping in the exporting of the No3.

I did my 1st dose of vodka tonight in hopes that it will start and to bring the nitrates down until I can find the cause. I will you keep you posted.
 
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