Po4 and continuous water change questions

waverz

Slave to the reef!
I have neglected my tank over the last 6 months or so and almost quit the hobby all together. It's a 60 gallon cube with a small sump.

I've decided to keep the tank setup and implement a few gadgets to make maintenance easier. I added continuous water change and ato system using a litermeter. The system is working flawlessly so far.

I tested the water and noticed my no3 and po4 levels where very high.

No3=80
Po4=2.18 ppm using Hanna checker

I've been doing 10 gallon water changes daily for the last few days. No3 and po4 levels have dropped some but are still on the high side.

I hooked up a gfo reactor today and have considered doing a few large water changes to aid in po4 export. With po4 levels that high I don't see my gfo laying very long.

My concern is overdoing it with the water changes. Is this something to be concerned with even though they are happening very slow throughout the day?

Any advice would be great.
 
I can't calculate the cost, but with a phosphate level that high, I'd look into lanthanum chloride. You probably will need to change the media every day for a while. If the cost is okay, then GFO will work, though. You can test the water coming out of the reactor to see when the media is exhausted. Regenerating the media will save some money, too, although it requires working with toxic chemicals.
 
You don't describe the condition of the tank but the following will get you ahead of the game while the GFO or LC do their job:

-Siphon out detritus.
-Blow off debris from the LR with a power head or turkey baster & filter it out with a sock or filter pad.
-Phusicslly remove any pest algae in the tank and filter or siphon any rememanfs, if applicable.
-Run carbon. You may need to change it out frequently as you most likely have high levels of dissolve organics.
-Consider skimming wet.

It's some work but worth the effort as it could speed up your tank's come back & you can back off once nutrients drop, which might take a few weeks. Good luck!

If you're changing over 10% of your water daily, yes that is a lot. Too much ? Not sure but doing it throighout the day sounds like the way to do it. If the livestock isn't showing signs of distress I'd guess it might be helpful for a short time.
 
The tank looks very clear and there isn't a single sign of algae.

I blew the rocks of with a power head yesterday as well as changed filter socks.

I did a 30 percent water change and am going to continue to do 10 percent daily until the no3 level is back to 0.

I haven't checked po4 levels yet but will later today. I'm curious on how well the gfo works over a 24 hour period.

The coral haven't seemed to be bothered by the large amount of water changes nor have the fish.

Looking forward to getting my water chemistry back up to par so I can restock the tank with sps.
 
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I can't calculate the cost, but with a phosphate level that high, I'd look into lanthanum chloride. You probably will need to change the media every day for a while. If the cost is okay, then GFO will work, though. You can test the water coming out of the reactor to see when the media is exhausted. Regenerating the media will save some money, too, although it requires working with toxic chemicals.

I just read about lanthanum chloride. I never knew it existed until today. I guess I have some research to do. Thanks for the tip.
 
I just read about lanthanum chloride. I never knew it existed until today. I guess I have some research to do. Thanks for the tip.
give the gfo three days and you should see a dramatic decrease. then monitor it daily. if it bottoms out and dosent decrease to zero in 7 days change out the gfo
 
Sounds like a fine plan to me. I'm only running a cup of gfo at a time so cost shouldn't be too much of an issue.
 
I use PHOS free from the pool store and it works great. Pretty cheap too!

After doing a little (very little actually) I think I may just stick to GFO and water changes. I've got plenty of salt and plenty of GFO on hand so might as well use what I have.

Thanks for the suggestion though.
 
Just checked po4 again after 24 hours of running gfo. Looks like it's down to 0.87 already.

I'll keep checking until I see an increase and then change out the gfo with new.

My goal is to keep po4 levels in check with 1 percent daily water changes and remove the gfo reactor.

While I don't mind running the reactor,I just don't have the space or outlets for that matter. I had to unplug my kalk stirrer just to run the reactor.
 
Once the phosphate is in your target zone, the water changes might keep it in the reasonable range. As long as you don't mind the cost, GFO and water changes probably are the safest way to get there.
 
Once the phosphate is in your target zone, the water changes might keep it in the reasonable range. As long as you don't mind the cost, GFO and water changes probably are the safest way to get there.

I'm just really glad I don't have a large tank with this issue. I can see where it would get costly very quickly using this method

I have fairly light bio load so hopefully the daily .7 gallon water changes will keep the po4 and nitrate levels in check. If not I may need to add another power strip so I can run my kalk stirrer and GFO reactor.

So much for trying to keep the system simple.
 
Are there symptoms of a problem that you are trying to treat, other than just the observed numbers (which may or may not be accurate, and may or may not actually matter)?
 
Are there symptoms of a problem that you are trying to treat, other than just the observed numbers (which may or may not be accurate, and may or may not actually matter)?


Like I mentioned in the original post my tank has been neglected. I lost a couple fish, very rarely did water changes, never changed filter socks, ect.

I was going to take it down and take a break from the hobby but instead I decided to purchase a litermeter in order to at least take some of the manual labor out of the equation.

I was able to to get the LMIII running and decided to check my water parameters and found NO3 to be to high to read (API) and PO4 of over 2ppm (Hanna PO4 Checker).

There has been a few spots of cyano and some very minor green slime algae on a few frag plugs. Along with that there is a colony of zoanthids that have been closed for several weeks.

So yeah, now I am kind of chasing numbers. The goal is to get the parameters back in check and purchase a bunch of SPS frags at an upcoming frag swap here next month.
 
OK, but the fish didn't die from the elevated phosphate. If algae or cyano is actually a significant problem, then it is worth reducing the phosphate, but otherwise, it may not be. Despite the usual good recommendation to keep phosphate low, some people have wonderful tanks with phosphate that high. Algae in those tanks may be iron limited.
 
Glad you stopped in again Randy. That paradigm tweak benefits from comment from one of your stature. . I remember when you first advised of of the study on enhanced growth with high PO4 over a year ago. You are a very highly trusted source .I don't think I could keep the aquariums I do without having studied your contributions closely over the years.
I'm still not to clear about the significance of the alteration in the cacification process as evidenced in decreased density of coral skeletal mass at high PO4 levels at least in the longer run. Do you think extra PO4 leading to less calcium carbonate crystal growth is the sole reason for increased growth or does higher PO4 also help the coral get more ATP to lay out more calcium carbonate ?

FWIW,. My aquariums do best with some phosphate and some nitrogen never went for the so called ulns methods;2.18ppm PO4 and 80ppm nitrate would still concern me though.
 
I agree that the phosphate won't harm fish or even soft corals, but if you're still interested in SPS (Acropora and the like) or other stony corals, the phosphate level might be more critical. I'm not sure whether you're still considering that.
 
I would like to keep mostly SPS which was the reason for my low target Po4 levels. I understand running levels too low is undesirable but to me 2 ppm seemed out of range.
 
FWIW, my sps of a wide variety of types do very well with PO4 ranging from .02ppm to.04ppm ( as best as I can measure it with the hanah 713 colorimeter) and NO3 between 0.2 and 0.5ppm per the salifert test. Those levels also limit nuisance algae enough for my taste.
 
FWIW, I'm aware of at least one tank that has very beautiful SPS and other hard corals, and it remarkably has nitrate over 50 ppm and phosphate well above 1.0 ppm:

http://www.reefcentral.com/forums/showthread.php?t=2366953

Here's a pic from it:

FTS-combo-sm.jpg


So clearly there is a lot more to the issue than just the numbers. :)
 
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