my thoughts on phosphates
- Thread starter ryeguyy84
- Start date
nutfluff
Member
I've had the same issue but started to run GFO in a reactor and the hair algae went away after a few weeks. You may have to change out your GFO weekly depending on how high your Phosphates were. My question is that in the battle of high phosphates as it related to nuisance algae... will the algae die off raise phosphates?
Do you have elevated nitrate?
ryeguyy84
New member
That was my original question. It seems like a vicious cycle
Removing live or dead algae will help reduce the issue, and once it is gone, then that issue is unimportant. 
nutfluff
Member
Thanks Randy... In response to breaking the cycle... When I change my GFO it takes about a week to for Phosphates to rise again. I would imagine if you stay on top of your phosphate/nitrate removing media and water changes you can break they cycle and the algae would eventually go away...?
Yes, enough GFO replaced often enough can almost always get rid of an algae problem. The concern is sometimes more the other way around: can you keep phosphate from being too low with such extensive changes that other creatures suffer.
dzrtrataz
New member
No Nitrates are at zero. Phosphates are the only thing that is high. I'm trying brightwells phosphater now. It's starting to come down. Will keep checking and see how it goes.
I pull the what hair algea I can when I have time or the day I'm doing a water change.
OK, let us know what you find.
grouper therapy
Member
In addition to the GFO, adding less food and increasing other export methods are about the only options.
Question Randy
Although water changes obviously do not remove the phosphate that have bind to the substrate, would not water changes remove the phosphates in the water column or at least the portion removed ,immediately? If that takes the level down enough for the phosphates to then enter the water column again and then another water change done removing them again. Repeat repeat so on so on. Is that not just as effective as other export methods given enough water changes are done?
Yes, repeated large water changes will eventually eliminate the bound phosphate.
grouper therapy
Member
It would not be easy to do a cost comparison since it is not clear how much phosphate is bound to rock and sand in any given tank, so one cannot really determine how many water changes of what size might be needed, or exactly how much GFO.
But IMO it is almost certainly going to cost a lot more by water change. A 100% water change in my tank would take a 200 gallon box of IO. Even if it only took 5 of these full changes to adequately deplete phosphate if starting at, say, 0.25 ppm, that's about $250. I think I can very easily drop phosphate very low in my tank using $250 of GFO, even if it started quite high and had a lot bound to rock and sand.
But IMO it is almost certainly going to cost a lot more by water change. A 100% water change in my tank would take a 200 gallon box of IO. Even if it only took 5 of these full changes to adequately deplete phosphate if starting at, say, 0.25 ppm, that's about $250. I think I can very easily drop phosphate very low in my tank using $250 of GFO, even if it started quite high and had a lot bound to rock and sand.
grouper therapy
Member
I guess the big question would be how much GFO it would take to remove the same quantity of phosphate as the theoretical 5 big water changes plus what was being introduced in the interim. You would also want to back out the cost of the regularly scheduled water changes as well. Correct? Although all of this is speculation because as you stated there is no way as of yet to determine the total amount of phosphates in a system .
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grouper therapy
Member
Is there any data available as to the capacity of gfo and how much phosphate can be removed in x amount of time based on x amount of flow through the reactor?
grouper therapy
Member
What is it that you don't think I get? Because you say it, that should be the end of it? Advancements and learning takes place when discussions are held with either opposing or differing views. Now as far as your blanket statement on the other forum that water changes do very little to remove phosphates is simply nonsense and inaccurate. That said ,water changes may not be the most efficient means but they are effective. I have seen no data to support the theory that GFO is the most efficient, only opinions that I highly respect but do not take as an undisputed fact. If you can accept them then enjoy your intellectual contentment. I prefer to expand and learn.
The amount of phosphate that GFO can bind is a function of the final phosphate concentration you want to get to. You bind a lot when the phosphate is 3 ppm, and bind very little when the phosphate concentration is 0.01 ppm.
But empirically, many reefers know that they can bring the phosphate concentration quite low with $100 worth of GFO, and in fact, need to be cognizant of overdoing it, which happens reasonably frequently, while $100 worth water changes just doesn't do the trick for most people.
But empirically, many reefers know that they can bring the phosphate concentration quite low with $100 worth of GFO, and in fact, need to be cognizant of overdoing it, which happens reasonably frequently, while $100 worth water changes just doesn't do the trick for most people.
