Greg, I was toying with setting up a refugium and decided against it for that exact reason. Caulerpa, or for that matter any macro algae die-off can be disastrous. I would try growing a small amount of it first before jumping in all the way.

------------------
We as hobbyist need to respect the reef, educate and learn so that it will live on for all to enjoy.
bajathree
http://home.earthlink.net/~amariquit/bajathree/

Having researched the Refugium method of filtration,I have found that the benefit's really don't out weigh the maintenance that has to be done to the algae crop to allow for the algae to be an effective form of filtration for the main tank.The caulerpa has to be pruned to avoid die off, if there is die off the nitrates and phosphates are released back into the system,which is what we are trying to avoid in the first place.When you use Caulerpa you are trapping the nitrates and phosphates, they are not being eliminated.With the sand bed the nitrates are diffused in the bed and converted to nitrogen by the bacteria, no more nitrates.You get the same benefit's as using the Refugium method, when you have live rock in the tank or any surface that has coralline growth on it,I have massive amount's of coralline algae on my tank walls and rock, or any thing else that goes in my tank.The Refugium method is great for growing a food source for fish or the raising of fish or invert fry.I have designed Refugium tank's for friends to grow their own food or raising cleaner shrimp.I really don't see the need for all the extra plumbing and pruning to get rid of nitrates, when a sand bed and live rock are doing the same thing.As far as providing a stable amount of oxygen at night,this is one of the benefit's of protein skimmer use.[img]/ubb/goldfish.gif[/img] [img]/ubb/biggrin.gif[/img] [img]/ubb/fish.gif[/img] Greg

[This message has been edited by Greg Montalbano (edited 07-14-2000).]

bajathree,

Caulerpa, or for that matter any macro algae die-off can be disastrous

Disastrous? macroalgae going sexual?



------------------
My webpage Updated 3rd July 2000

Greg,
first of all, you are confusing two very different concepts and setups here:

Having researched the Refugium method of filtration

Refugiums are REFUGES for micro and macrofauna mainly as you said above, not filters.
You are confusing algae tanks, algae scrubbers, and macroalgae growth for nutrient export with refugiums.
Two different concepts, two different goals, two different setups [img]/ubb/smile.gif[/img]

The caulerpa has to be pruned to avoid die off

Will it avoid the die off? wasn't it the 24/7 lighting according to Mike Paletta?
Accoding to Bob fenner, caulerpa macroalgae stops growing when nutrients are low in the tank, but doesn't die off because of that.
Have you seen Fish Whipererer's tank? he posts at AL and RC too.

You get the same benefit's as using the Refugium method, when you have live rock in the tank or any surface that has coralline growth on it,I have massive amount's of coralline algae on my tank walls and rock, or any thing else that goes in my tank.

You mean coralline algae does the same caulerpa macroalgae does in an algae scrubber or macroalgae filtration system?
If so, why don't you remove the coralline algae for nutrient export?

As far as providing a stable amount of oxygen at night,this is one of the benefit's of protein skimmer use.

Have you seen the charts in page 198 of FAMA magazine, July 2000 issue?

In case you didn't:
Figure one shows a comparison of system pH and 'coral' pH under conditions of good water motion.

In the chart you can see that pH in the system drops from 8.4 to 8.1 at night.
When the lights go on, pH jumps in just *2 hours* from 8.1 to between 8.5 and 8.6

You know oxygen and pH are related. What you are looking for is to avoid pH swings having high amounts of dissolved oxygen in the water, that's why you use 24/7 or at least RWD photoperiods over algae tanks.
And as you see, skimming alone doesn't compensate, since there is no photosyntesis at night--->less oxygen--->pH swings

Joaco

------------------
My webpage Updated 3rd July 2000

I was going to use a refugium to grow my Tang Heaven in. Instead I set it up in a 10 gal. by itself. I had a 25% die off the first week. That would have been disastrous if it were part of my tank. My levels in the 10 gal after the die off were off the scales.

------------------
We as hobbyist need to respect the reef, educate and learn so that it will live on for all to enjoy.
bajathree
http://home.earthlink.net/~amariquit/bajathree/

Do you have strong skimming in that 10 gallon tank, and did you remove the macroalgae as you saw it dying?

The release of spores by sexual reproduction of caulerpa macroalgae can easily be removed with skimming before it releases what the macroalgae tissue absorbed.

You grow Tang Heaven as tang food, not for nutrient export in an algae tank/scrubber system. Different macroalgae, different goal, different setup to grow it in [img]/ubb/smile.gif[/img]

Macroalgae used for nutrient export is Caulerpa sp., Tank Heaven comes with Ulva sp. and Gracilaria sp.

The initial die-off you experienced is somehow normal as the macroalgae is exposed to different conditions when it was shipped, including lack of light and temp differences, not to mention osmotic changes too [img]/ubb/smile.gif[/img]

Joaco

------------------
My webpage Updated 3rd July 2000

[This message has been edited by Joaco (edited 07-15-2000).]

Originally posted by Joaco:
Greg,
first of all, you are confusing two very different concepts and setups here:

Have you seen the charts in page 198 of FAMA magazine, July 2000 issue?

In case you didn't:
Figure one shows a comparison of system pH and 'coral' pH under conditions of good water motion.

In the chart you can see that pH in the system drops from 8.4 to 8.1 at night.
When the lights go on, pH jumps in just *2 hours* from 8.1 to between 8.5 and 8.6

You know oxygen and pH are related. What you are looking for is to avoid pH swings having high amounts of dissolved oxygen in the water, that's why you use 24/7 or at least RWD photoperiods over algae tanks.
And as you see, skimming alone doesn't compensate, since there is no photosyntesis at night--->less oxygen--->pH swings

Joaco

I have to correct you on this with a protein skimmer you are oxygenation the aquarium water even at night.The ph swing is related to oxygen content,which I agree with you on this,but with the protein skimmer,refering to the ones that empty the skimmed water directly to the tank,you are getting a constant supply of oxygenated water to compensate ph swings due to low oxygen content at night.Now as far as confusing algae scrubbers with refugium type filtration systems, they are both the same, the only difference is how the water is introduced to the algae colony, one is under water and the other is a soak and drain off principle. Now both algae colonies are exposed to the water for the removal of nitrates and phosphates, and both provide the nutrient export principle, and both are exposed to the 24/7 light principle.Again absorbing, but not elimating the unwanted nitrate and phosphates just locking them up.Then pruning is involved to avoid die off and to avoid leaching nitrate and phosphate back into the system.Here is a simple formula for all types of filtration system's.They all work, but require specific maintenance to maintain peak performance and to avoid system failure.With the algae scrubbers and refugium system's they are providing the same filtration properties as live sand and growing live rock,again refugium's are great for the growing of algae for feeding and grow out tank's for inverts, but I see no reason to tie them into existing system's for nitrate control.[img]/ubb/biggrin.gif[/img] Greg.

Hi All,

Just thought I would add a few thoughts about refugiums/macro algae filters.

I have been playing with macro algae filters in various configurations since the early nineties.

It has been hit or miss regarding keeping the macro algae from going into a sexual crash, until I tried the methodology where the algae is illuminated 24/7.

Some of my observations to date:

1 I had the most trouble keeping macro algae in heavily skimmed systems, i.e. an ETS 1000 on a 135 for example. Whether this was related to lack of a particular nutrient etc. is TBD.

2 A sexual crash was not a disaster for any system that I have had experience with. A good skimmer would take care of the release, and the corals fed as if the were given a dose of plankton.

3 Systems with the macro algae illuminated 24/7 has to date, never crashed on me.

4 The macro algae seems to grow in fits and starts, related to nutrient spikes etc.

5 The system pH in systems with the macro algae illuminated 24/7 was the most stable that I have experienced. In my current system, the daytime/nighttime pH only varies typically 0.05 pH units. (as charted by my aquacontroler) I would add that my alkalinity is not particularly high.

6 Oxygen production, as evidenced by bubble forming on the algae, is highest during the dark cycle on the main tank. I believe that this is because of increased CO2 production by the main tank. This CO2 link is similar to my experience with fresh water plant tanks and CO2 supplementation.

My current system which is just over 1 month old, utilizes live rock, a 6” deep fine live sand bed, an EcoSystem style algae filter/refugium, and no skimmer.

The macro algae in the EcoSystem filter as grown from a cluster the size of my fist, to almost completely fill the filter. My bio-load at the moment consists of only live rock, a lawnmower blenny, and a cleanup crew.

I guess I am exploring the concept that a system that utilizes live rock, a deep sand bed, and an algae filter/refugium will constitute an "optimum" “no skimmer” approach.

Regards,

Scott


------------------
The definition of an expert is a washed-up drip under pressure.

With the set up you have the only benefit's the algae will be doing is the control of ph swing's at night and the addition of oxygen.Having the skimmer on as you said caused problem's due to the fact that there is a functioning sand bed.With the skimmer going and the sand bed, the competition for nutrients was starving the algae.With an increased bio load of fish and inverts you will be able to use your skimmer again without worrying about starving the algae,also the skimmer will remove the yellowing gelvin that is produced and any algae spores,that may be produced.Also having the sand bed you won't have to worry about pruning the algae, if there is die off any nitrate that is leached out will be diffused in the sand bed,so you really are covered in all areas of filtration for this new set up.If I was to add a refugium to any tank I would have a sand bed also to control any shifts of nitrate due to algae die off. [img]/ubb/biggrin.gif[/img] Greg.

Greg,

One of the reasons that I chose to experiment with this methodology is so I would not use a skimmer.

I have seen these systems work very well with even a high bio-load. I believe the addition of a live sand bed will only further add to the nutrient processing capability of the system.

I am particularly interested in trying to keep (long term) gonipora and Heliofungia, which I had my best luck with in skimmerless systems. Indeed when kept in an algae filtered system, I had a gonipora that I traded back to the LFS because it outgrew my tank.

The previously mentioned attempts to keep macro algae happy in the system that had the ETS 1000 skimmer, was on a tank with a relatively high bio-load, but not a deep live sand bed as this methodology was unknown to me at the time.

Also, stable pH/higher oxygen levels, and home grown Caulerpa, would be enough reasons to keep an algae filter, even if these were the only benefits provided.

Regards,

Scott

------------------
The definition of an expert is a washed-up drip under pressure.

Greg,

I have to correct you on this with a protein skimmer you are oxygenation the aquarium water even at night.

Sorry, I think you misunderstood what I said. What I said is:

"And as you see, skimming alone doesn't compensate"

With protein skimming you oxygenate the water at day and night, but the skimming at night still doesn't compensate the oxygen amount dissolved in the water, because as I already said above, there is no photosyntesis at night-->less oxygen.
If the skimmer is running 24/7 it won't increase oxygenation at night, since it has the same effect 24/7.

The ph swing is related to oxygen content,which I agree with you on this,but with the protein skimmer,refering to the ones that empty the skimmed water directly to the tank,you are getting a constant supply of oxygenated water to compensate ph swings due to low oxygen content at night.

Again, the difference in dissolved oxygen is noticed by the lack of photosysntesis and the skimmer doesn't compensate. The constant supply of oxygenated water you get from the skimmer is the SAME one you get during the day.
Oxygenation takes place by gas exchange at the air/water surface, that's how a skimmer helps in water oxygenation.

Now as far as confusing algae scrubbers with refugium type filtration systems, they are both the same, the only difference is how the water is introduced to the algae colony, one is under water and the other is a soak and drain off principle.

You keep confusing refugium with filtration...it's not the same [img]/ubb/wink.gif[/img]

Then pruning is involved to avoid die off and to avoid leaching nitrate and phosphate back into the system.

Pruning takes place for nutrient export from the system.
If phosphates and nitrates are locked up in the tissue of the macroalgae and not consumed, what does the algae feed on? what is it doing photosyntesis for? how does it grow if it's not consuming but only accumulating? what does it consume then and where does the new algae tissue come from?

With the set up you have the only benefit's the algae will be doing is the control of ph swing's at night and the addition of oxygen

Only? I agree with Scott, good enough reasons even if these were the only benefits!

Joaco [img]/ubb/biggrin.gif[/img]


------------------
My webpage Updated 3rd July 2000


[This message has been edited by Joaco (edited 07-18-2000).]

First let's go into protein skimming,oxygenation occurs inside the actual skimmer itself, with the constant bursting of air bubbles inside the water body that is one of the benefits of skimming.With skimming the water is oxygenated day or night and it does compensate the night phase of an aquarium with the drop in oxygen.You said yourself there is no photosyntesis at night-->less oxygen in the tank, so the skimmer will make up the oxygen content at night as well.Also oxygenation is not limited to only air/water surface agitation,the skimmer is a proof source of that.Okay back to confusing Refugium with algae scrubbers,Refugium is filtration! the moment you connect that pipe to your main tank the tank's nutrient's[nitrate-phosphate are effecting the algae,which is absorbing -living off these nutrient's.The ph is effected, the oxygen content is effected,if you don't prune, the main tank is effected with leaching of said agent's.Okay you are also providing a safe place for the cultivation of the micro fauna, but that occur's in the main tank as well,the only difference is the level of predation on these creatures.With the algae scrubber you are doing the same, no matter what species of algae you are using there is no discrimination on species here.All provide the same function in the enclosed system,both are exposed to water, both are exposed to 24/7 light cycles.Both provide the same end product.Now we go to pruning the algae, which is done for nutrient export from the main system,some of the nutrient's are used by the algae in it's life cycle to grow.Joaco you are confusing the actual refugium principle, what I mean by this is if you had a refugium not connected to your main tank, and were growing micro and macrofauna as you stated you were doing with the Refuge,then I would agree with you that a Refugium is not filtration, but it is connected and the main tank is being effected by the addition of this algae system.So what you have is an algae scrubber that is underwater, the moment you connected it to your tank you are using it for filtration-both are now one.Now another reason you guy's are using the refugium principle is to keep species of coral's that don't do well with protein skimming,I have never had that problem, I have an organ pipe colony for 3 years, and no problem and they are said to be a difficult coral to keep, as well as other species that are doing great.You have to remember you are dealing with a closed system that has a concentration of life that is really to great for the amount of water in the actual tank.That is why we strive to try new filtration method's to maintain these large captive colonies.That is why I use the filtration system you posted, because it super oxygenates the water day or night and it provides great water current without having to purchase extra powerheads.And the media underwater grow's alot of life to help with the break down of the bioload.[img]/ubb/biggrin.gif[/img] Greg [img]/ubb/fish.gif[/img]