Controlling Phosphates

Diddle822

Cleaner Shrimp
M.A.S.C Club Member
#1
So what does everyone do to control phosphates ... I've heard gfo reactor. If that's the case what size for a 72gallon tank. Also heard phosphate rx... 
 

Sour137

Cleaner Shrimp
#2
I used GFO on my first tank, absolutely nothing wrong with it, and there are ways to reuse it after using it the first time. On my current 75, I grow chaeto in my sump. I've been testing my phosphates since may and I've never had any show up on the red sea algae control test kits, and I have three hungry-all-the-time anthias. Right now the ball is about the size of an heirloom tomato, and I use the kessil h80. I suspect I would get a better growth rate with a better light. For the price, and the seeming lack of testable phosphates my money is on chaeto.
 

jda123

Dolphin
M.A.S.C Club Member
#4
There are a handful of ways, but first you need to figure out what is causing the phosphate in the first place. The remedy might be different.

2.48 is deadly high. Are you sure that is right?

The most current common cause is dead/dry rock that has bound up phosphate from terrestrial sources where it was mined. Not all dry rock has this, but the majority does. Rock that was in somebody's tank and dried out nearly always is full of phosphates - people who keep phosphate-free tanks don't just dry out their rock. Did you happen to use dead or dry rock?

Overfeeding and not doing routine husbandry for years can also lead to high phosphates. In this case, the aragonite is usually bound full-up with phosphate and acts like a seemingly never-ending supply. This can take a LONG time, though.

Does any of this ring true at all?

I am going to hold back any recommendations until we can identify the source, but P of 2.5 might kill the chaeto or even stop photosynthesis and you might need to lower it other ways first.
 

Diddle822

Cleaner Shrimp
M.A.S.C Club Member
#5
So I used all live rock that was never dried. Still relatively new tank. This was my first test for phosphate so I'll have to try the test again. I try not to overfeed and do weekly water changes/ cleaning. 
 

Sour137

Cleaner Shrimp
#7
Diddle822;n676999 said:
So think Chaeto is a better bet then? Im testing like 2.48 with the Hannah checker ...
I wouldn't necessarily say better. Both options have drawbacks. For GFO, it has a lower initial investment, but an ongoing cost of buying GFO, or bleaching what you have to reuse, however even with that method, you will still need to buy GFO from time to time as it will break down gradually. Chaeto has a higher initial investment in lights, more so for a good light, but no ongoing cost. Chaeto can be bought for cheap from an LFS or acquired from another reefer for free. My presumption, and I'm not an expert, is that the Chaeto is less responsive to sudden spikes in phosphates as it takes time to consume the phosphates in the water column. Combined, both will work but one will gradually become redundant. Either the GFO will take all the phosphates and leave none for the Chaeto, or the Chaeto will do the same leaving none for the GFO, I presume the former. If phosphates are as high as that test would seem to indicate I would definitely go with the GFO as that will have an almost immediate effect. For me, I bought Chaeto with the first fish I got for this tank, and I have been growing it gradually ever since. I didn't always have a test kit for phosphates, but by the time I got one, none were showing up. I've only ever lost inverts in my tank, and never had a fish death so the haven't been any phosphate spiking events so I'm not sure exactly how responsive Chaeto is, but I think it is safe to assume that it is not as responsive as GFO, perhaps someone more knowledgeable than myself has some input on that.

As far as the phosphates are concerned, I would think that in 6 months time the initial fauna from the wet rock would have had time to die and decay. That would be the obvious source of phosphates, and with regular water changes, ideally more than once per week if the test turns out to be true, that should diminish.

My preference is to go as organic as possible. I know the Chaeto is always doing it's thing, and I don't have to worry about it becoming saturated between tests and spiking, like GFO can. I will say the carbon gfo kit from brs can be easily cannibalized for parts, and the two stage can be quickly converted to a one if you go Chaeto + carbon, which is what I do with mine. This morning I used the ball valve and rigid piping that came with my two stage for the drain on my skimmer. I have an automatic neck cleaner and it is a pain to remove that sucker to empty the cup, and I had a pretty dramatic overflow of my skimmer drain bucket which sucked.

My very amateur advice would be to get both the two stage carbon + GFO filter, and the a small light for growing chaeto, and transition completely to one or the other in some more time. My tank is about 9 months old, with livestock in it for 6 months on Friday, so I still have a lot to learn, but that is what I have learned from a past build (GFO), and this build (chaeto). Definitely follow jda123's advice as he appears to more about this than I do.
 

jda123

Dolphin
M.A.S.C Club Member
#8
Where did you get the rock from? Was it direct from the ocean, or was it in another tank before? If the rock was used and abused, it might take a 5G bucket of GFO to get all of it out. If the rock was direct from the ocean, then the test just might be bad.

In any case, you are going to need to change a lot of water and use a lot of GFO for a while. P that high is a toxin for inverts. When you get the P below 1, and .5 would be even better, then Chaeto might be able to do something.

What will happen is that you will have tank water P at 2.5, assuming that the test is accurate. Say you change 50% of the water. Tank P is now at 1.25. A day or two later, it is back up to 2.49 as the rock let go of a bunch more phosphate. ...and then you start the cycle again. It takes a long time to get it down, but it will if you are diligent.
 

Diddle822

Cleaner Shrimp
M.A.S.C Club Member
#9
I got the rock from someone on here he cleaned is good and it was sitting in a garbage can with heater and powerhead etc for a while. Don't think it's from my rock... could be wrong of course ... maybe just my lack of knowing that caused this. 
 

jda123

Dolphin
M.A.S.C Club Member
#10
Put a piece in a bucket with a few gallons of freshly mixed saltwater and a powerhead. Test the water in a week for phosphates.

People with really nice rock usually don't sell it or let it go. I have probably 500 lbs of phosphate free rock from over the years and you would have to pry it from my cold, dead hands. I moved it from Missouri with me... the stuff is precious. When people sell rock, it is always like "highway miles." Nobody ever tells you the real story.
 

NickP

Clown Fish
M.A.S.C Club Member
Platinum Sponsor
#11
jda123;n677219 said:
Put a piece in a bucket with a few gallons of freshly mixed saltwater and a powerhead. Test the water in a week for phosphates.

People with really nice rock usually don't sell it or let it go. I have probably 500 lbs of phosphate free rock from over the years and you would have to pry it from my cold, dead hands. I moved it from Missouri with me... the stuff is precious. When people sell rock, it is always like "highway miles." Nobody ever tells you the real story.
I sold him the rock. As you remember you helped me with issues with that rock a couple of years ago. If its the rock giving him trouble I'm gonna feel pretty bad...:(
I wasn't have any issues with it for the last year or two. Didn't even run gfo anymore as the levels in the tank stayed around .02 with a hanna checker phosphorus and did regular water changes.
I wouldn't have sold it if I thought there was issues with it,had no reason to suspect that was the case. I actually was planning on using it but ended up with way to much.
 
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