Anybody quit GFO and live to tell about it?

[Pittsburgh]

Could you provide some sources for this? I've seen a study or two that showed iron oxide hydroxide to release bound phosphates when the phosphate levels in the water column dropped suggesting the sequestering isn't permanent, much like phosphates bound to live rock.

From this article by Randy Holmes-Farley



He found it from this study:

3. Phosphorus phases in the surface sediment of the South Sea. Son, Jaekyung; Lee, Tongsup; Yang, Han Soeb. Dep. Marine Science, Pusan National Univ., Pusan, S. Korea. Han'guk Susan Hakhoechi (1999), 32(5), 680-687.

Some time in the past I thought I had read another one that confirmed this but my google-fu isn't working for me this morning.

Yeah, I remember reading his article as well. Too bad I can't confirm the source as the original paper (3) is in Korean. I'll try to dig up other studies I found in the past over the weekend. AFAIR, the deal is that while the bond is indeed not permanent, with GFO it is still strong and holds for many many months. In other words, unless you keep the same batch of GFO on line for a year or longer, you won't see any noticeable leaching of any kind. And even when it starts breaking, the release happens in small fractions. When I did my tests (and I had a lot of phosphates originally) the output of the GFO reactor, 2-3 weeks after the media was completely exhausted, measured no higher than phosphates level in the tank water. I was doing daily tests with hanna checker, fwiw. My tests are all subjective of course as one may argue that phosphates in water were due to released phosphates from GFO reactor. I would expect them to be higher coming out of the reactor if GFO were leaching phosphates back at any reasonable rate. The accuracy of my hanna checker is also questionable, of course.

 

[jerpa]

Just curious as to why you emphasized the "after the fact" phosphate removal. I'm not aware of that many mechanisms for the "before the fact" phosphate removal. Even with a filter sock or chemical binders, you need phosphate in particulates before you can remove them right? Or with a skimmer, ortho must be first converted/bound to organic compounds and even then, under ideal condition, less than 30% or so can really be removed...

Phosphates will be present in leftover food and fish waste but it is organically bound at this point. The phosphates are present in the aquarium but they are not present in the water column to feed nuisance algae. Skimming, filter socks, and detritus removal export these phosphates before they are released assuming they are implemented properly. GFO removes the phosphates that are released into the water column itself after the waste breaks down.

 

[hypnoj]

Back to the OP's question. Nobody wants to run GFO, and I'm sure many people can get away without it based on their other reefkeeping habits. I personally can't go without it based on my feeding habits and care.

 

[Reefin' Dude]

I agree that attacking the detritus before it can break down is the most effective way to run a system without GFO, but some inorganic phosphates will always be present. I still believe a small amount could be valuable in preventing the live rock and sand from becoming saturated with phosphates over time. Just to be clear that is purely my own opinion based on no scientific evidence whatsoever.

i do not understand what you are saying? calcium carbonate can only bind inorganic phosphates. how is a small amount going to keep it from absorbing more? it is either going to absorb or not. the ability of the bacteria to release it from the calcium carbonate matrix on the other hand is dependent on other resources. the object is to limit P, but not the other resources needed by the bacteria in order for the bacteria to utilize the P instead of leaving P to bind to the matrix.

Just curious as to why you emphasized the "after the fact" phosphate removal. I'm not aware of that many mechanisms for the "before the fact" phosphate removal. Even with a filter sock or chemical binders, you need phosphate in particulates before you can remove them right? Or with a skimmer, ortho must be first converted/bound to organic compounds and even then, under ideal condition, less than 30% or so can really be removed...

the more you remove in organic form the less there is going to be in inorganic form. depending on the biotope wanting to be emulated this is either a good thing or an acceptable thing. there are other ways to trap detritus than the ones you listed. several of us on another forum are incorporating conical settling tanks into their systems. the cone end allows detritus to accumulate in a very limited area limiting the bacterias access to oxygen for decomposition. therefore slowing the rate of decomposition. allowing less inorganic phosphates to be released. the problem with filtersocks is that they trap the detritus and then keep it in a high flow area where the bacteria have a readily source of oxygen for decomposition. creating the perfect environment for releasing the inorganic nutrients and CO2. a double wammy.

Back to the OP's question. Nobody wants to run GFO, and I'm sure many people can get away without it based on their other reefkeeping habits. I personally can't go without it based on my feeding habits and care.

i fed 5 times a day. it all depends on how the system is setup. is it setup for nutrient removal or nutrient capture? unfortunately the way most people recommend how to setup their systems creates a system that is better at nutrient capture than nutrient removal.

G~

 

[Osteoclast]

I agree with Gs philosophy regarding nutrients. I skim and rely on GFO without other methods to support my system. I tend to the sand weekly which in my tank is less than one inch and focus most of my attention to its upkeep by manual methods. The idea of a settling tank is appealing to me, would be easy to incorporate into the sump design, and itself provide a major mode of disposal. I believe that a BB system would be ideal for a settling tank due to the bottom flow required to suspend detritus. GFO might not be needed in this design if the detritus is suspended well and long enough to exit the tank.

 

[insomniac2k2]

I replaced GFO with LC. Does that count?

 

[jerpa]

i do not understand what you are saying? calcium carbonate can only bind inorganic phosphates. how is a small amount going to keep it from absorbing more? it is either going to absorb or not. the ability of the bacteria to release it from the calcium carbonate matrix on the other hand is dependent on other resources. the object is to limit P, but not the other resources needed by the bacteria in order for the bacteria to utilize the P instead of leaving P to bind to the matrix.

I may not have been clear. I believe running a small amount of GFO to bind any phosphates from detritus not removed will prevent the buildup of phosphates in the live rock. I believe that it is all but impossible to prevent any inorganic phosphates from being released. I believe GFO is another tool to complement our other filtration techniques, none of which are 100% effective.

 

[G4546]

to me chaeto dying off is a fantastic sign
g~

+1

 

[ANFPO]

Now that i have been using other methods to remove phosphates, i will be taking off my reacotor. It takes up too much space in my tiny 10gal sump. Servicing those reators becomes old quick. I rather dose lathanium or phosbuster. No hardware except your skimmer which you already have and maybe some filter floss.

 

[Ron Reefman]

LouH, I have a reactor plumbed into my system, but only run GFO or carbon when I need to. GFO for 6 weeks to nip an algae bloom in the bud and carbon for 4 weeks after using Flatworm Exit (unsuccessfully). There are lots of alternatives... some don't even require chemicals.

 

[symbiodinium]

I am new to keeping SPS and have been reading as much as possible on RC plus videos at BRS. I have a couple questions for GFO and Carbon, not removing them but I see that in this thread people limit use. How often do you run GFO if not continuous and when do you run carbon? I understand to remove and keep parameters in check but once there do you stop?

 

[Zobp]

Not a necessity to limit use. More than one way to do reefing. Some don't feel a need to run GFO all the time as Reefman stated use it to nip a algae bloom. I take my GFO offline and just using macro algae for nutrient export.

Carbon does't have to be run all the time, but since it is so cheap and highly effective for water clarity and many other things most run it all the time. Since you are growing SPS it would be a good recommendation to keep carbon running for the needs of better water quality.

 

[symbiodinium]

Thanks Zobp. I installed a BRS GFO reactor about a month ago, I just checked my phospates with Hanna checker and it read 0.00, don't know if that is possible but I pulled the GFO and filled it with reef carbon and will run that for a while. I'll monitor the PO to see if it rises.

 

[Meshmez]

I was having GHA issues, so I started running GFO for about 4 months. During that time, Chaeto would not grow, GHA wasnt going away. Finally decided to just pull the GFO. Chaeto grows now, GHA is subsiding... I think I'm feeding SLIGHTLY less, but nothing major has changed.

Corals seem to be doing better without the GFO. might just be the better water quality that is defeating the GHA though. Couldnt tell ya why the Cheato seems to be working better than the GFO did. It doesnt really make sense to me, but im just going by the lack of GHA..

 

[tommyz44]

I used LaCl for a while which worked well, but i highly sugest reading the guide on that. EVERY PAGE of it! anyway i actually switched to Zeovits which worked well and i've seen it work well in others tanks as well. I didnt buy the mega expencive setup either. I just use zeovits in a TLF reactor and on a daily basis i turn the ball valve to stop flow invert the reactor several times and turn the flow back on. this stirs up the gunk inside which is recomended to be done.

 

[speedo2wet]

I've never seen a change from running GFO. On my 220 I have nothing but LR for a filtration system and a reef octopus skimmer. I feed live bait shrimp, and frozen squid, clams, mussels, sardines. Pretty much anything I can get my hands on. The lights are t-12 and over 6 years old, so the spectrum is way off. The tank does not grow a bit of nuisance algae. All though the rock work is a homemade solution which could have something to do with it. On my reef I run a completely different system since no two are alike and I'm a trial and experimental guy at that. Still no GFO so it is possible to not utilize it, as long as the source of your problem is recognized. Even though an out break of bryopsis happened- that's an entire plague all on its own.

Ill tell you what I dose every now and again- Marc Weiss reef bugs and a bacteria, I'm more into researching natural ways to combat issues. Yet again look at the source of your problem.

 

[thereeftank]

I stopped several months back. I regenerated mine, but still went through a lot of trouble as it would clump up in the reactor in about a weeks time. tried different reactors and pumps.

I tried to go all refugium as some people have luck with that. That didn't lower phosphates enough for me.

As phosphates crept up I experiemented with LaCL. Works well. Didn't like to wash out the 5micron socks after each dose.

Currently dosing vinegar and nitrate dosing. Early stages of nitrate dosing. It seems to work for now. For the first time in months I have phosphates down to 0.00. I still have some small algae on rocks, but it's on its way out. I see more polpy expansion on my corals and more growth. Still have ways to go to "dial it in", but I'm GFO free for several months.

 

[Ron Reefman]

i fed 5 times a day. it all depends on how the system is setup. is it setup for nutrient removal or nutrient capture? unfortunately the way most people recommend how to setup their systems creates a system that is better at nutrient capture than nutrient removal.

G~

OK, so don't be so stingy with the info. Since 'most' of us do it 'for nutrient capture rather than removal', tell us how it should be set up.

 

[jerpa]

OK, so don't be so stingy with the info. Since 'most' of us do it 'for nutrient capture rather than removal', tell us how it should be set up.

The ideal system for dealing with detritus would include a very high flow, bare bottom display with rock work that allowed flow throughout the structure. There would be a good deal of vertical mixing within the DT itself feeding an adequately long flat-weir overflow. This would flow into a pre-sump conical settling tank. Reefin dude was the first person I heard it from and it is pretty ingenious I must say. I've been trying to think of a way of incorporating one into my setup as well. The water would then flow to a sump with a very large skimmer. The sump would also be barebottom and have enough flow so that no detritus settles.

FWIW this is all IMO.

 

[DiscusHeckel]

I have a 250-lt set up with a sump (net volume after displacement). I stopped using GFO on 28th May. Before this date I used to fluidise Rowa Phos in a Two-little fishes reactor. The reason why I stopped it was because my corals looked quite pale and had pastel colours. Phosphate readings with the Rowa Merck high sensitivity phosphate test kit was zero.

Today's phosphate reading is: 0<= P < 0.008 mg/l. I would say it is closer to 0 than 0.008 mg/l. By the way, nitrate readings with the Salifert test kit have been zero or very near to zero (I cannot see any pink hue in my test vial) for a very long time.

Here is the summary of my set up:

It is a mixed reef with four large clams (3 X T. crocea and 1 X T. squamosa). I fluidise Seachem matrix carbon in a reactor, keep a bag of Seachem purigen and a large lump of chaeto in my sump, which is kept under 2 X 36W (6500K) economy bulbs. I also use a Bubble magus NAC 6a protein skimmer and endeavour to replace 28lt tank water every week. I have the following fish, which I feed three or four times a day with flakes and frozen:

1 X yellow tang
1 X Genicanthus melanospilos
4 X Serranus tortugarum
1 X Helichoeres hortulanus
1 X Chromis cyanea
1 X Gramma loreto

Both my display tank and sump are bare bottom. I use 4 X Tunze 6055 nanostream pumps connected to a Tunze 7095 multi-controller. The pumps turn over the display volume (about 190 lt) about 78 times per hour (taking the programmes into account). No detritus settles at the bottom of my tank. However, detritus settles in my sump, especially in the chaeto section. I make no effort to collect detritus via mechanical means. However, I occasionally stir the chaeto and remove detritus from the sump via a pump while changing water.

Finally, I dose 1 drop of Salifert iodine every day, 12.5 ml of Kent Marine Super chelated iron every week to boost the growth of chaeto, which I harvest once every few weeks (around 3 litre when compressed in a measuring jug). I also dose 12.5 ml of Salifert Coralline aminoacids per week to feed the corals.

I get no hair algae growth on live rock or glass, which can distort phosphate readings. However, I have green bubble algae epidemic at the moment.

Finally, here is a FTS of my set up to show you the rock arrangement. As you can see, rocks are loosely put together and there are not many of them.

I am sorry that my post has been long. I thought I should give you a complete picture to enable you to evaluate my situation.