Decreasing phosphates

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Mebbid

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Mar 1, 2013
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I need some advice on dropping phosphates. I seem to be stuck at minimum 0.13 and can't seem to get it any lower, I use a new Hannah checker. My nitrates have measured at 0ppm for the last 2 weeks using a red sea nitrate kit.

My tank: 40g breeder with 2 clowns, 1 small fairy wrasse, and 1 smallish engineer goby at about 6" long. I feed a small amount of frozen food daily. 1 cube of mysis will last 4 - 5 days.

I run Gfo, activated carbon, a 110g reef octopus protein skimmer, and a refugium growing chaeto and grape caulerpa. I have an auto top off with 1tbsp of kalk per 5 gallons. My filters on my rodi unit are approx 1 month old.

Until the last week I was getting quite a bit of cyano growth. I have gotten that under control and now it's switched to hair and bubble algae.


Dies anyone have any suggestions to decrease phosphates just a little bit more?
 
how often do you trim your macro , the reason I ask macro die off could be just putting the phosphates back into the water . I trim back between a quarter inch to a half inch every week this helps them rejuvenate .

as the macros decompose over time there just putting the phosphates back into the water , this is why trimming is important the grape really don't work as well as some thin leafy macros exorbing nutrients . like Caulerpa Mexicana and similar types of macros , these type macros grow fast and needs constant trimming rejuvenating promoting new growth .

I just did my yearly cleaning on my sump god if you only saw all the decomposed macros that built up over time yes I found my phosphate problems . after cleaning my sump I made a vow every 3 months the sump gets a cleaning . now I also made 2 inch high shelves out of egg crate to raise the pumps and skimmer . so it's easier to siphon out the crude underneath everything in the sump before it builds.

this page should help give you a little help and understanding of most macro's marineplantbook
 
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What is your water source? Are you running ro/di unit or tap? It sounds like this may be your problem especially that you have a refugium and running gfo.
 
Sorry, been super busy and haven't hopped on in a while. I did the harvesting on the macros as suggested along with a big tank cleaning. I didn't see any changes in the phosphate over a weeks course. However I checked the phosphate levels this morning and they were at 0.00ppm. Checked them 3 times just to be sure so I am gonna decrease the amount of go I'm using.

If I were to guess, my rocks were leeching some phosphate along with the poor refugium maintenance. Thanks for the help guys
 
I have never been a believer in the rock leaching phosphates. If it was coming from the rock, it would have been some sort of decomp occurring inside the rock itself.
As for that phosphate reading, is still be skeptical. That is hard to do for even uln systems to obtain, to which 0.03 being as low as they want to go without consequences from a coral standpoint.
 
Calcium carbonate is used in the medical field as a phosphate binder for renal patients so it wouldn't surprise me at all if live rock absorbed it to some degree.

I'm also using 10tbsp of gfo in a 40g tank atm which was recently changed out.

I would hate to not be able to trust my hannah checker, but I will see if I can get it verified. The reagents are brand new and after adding them to the vial there wasn't any color change which in the past it turned noticeably blue.
 
It calibrates itself every test, but they do sell kits to double check the readings for accuracy. I might look into getting one of those.

I do know my LFS uses salifert, so I think that's gonna be my first stop.
 
In all these steps I suggest moving slowly and reduce P4 in small increments over time.
Rule number one- no rapid changes of anything.

I humbly suggest;

Step one
Confirm the Hanna readings. Worst thing you can do is launch on bad data.

Step 2
In a small system like this, try a different salt mix, confirm RO/DI is working and increase water exchanges. Don’t starve the fish, increase filtration and exchanges.

Step 3
GFO is effective in maintaining low P4 but can have difficulty reducing it quickly, this is a safety advantage usually. Think of it as a “shock absorber.”

Step 4
This is a more advanced way of reductions, but has to be done right every time. I have a 27 year old 300 gal. reef. Lots of fish and coral and I feed abundantly. I use a ATS and the Triton method with minimal water exchanges. I run GFO to maintain low P4, but bi-weekly I do a Lanthanum Chloride dose. Making a 0.02ppm reduction over four hours. I can repeat daily to hit my target of 0.05ppm. But never more than 0.02ppm in 24 hours. You can read about it on my thread. I take great care in it’s use, but it is the most effective “calibrated” way to remove phosphates I’ve ever seen. Makes your GFO last a long time.

But in your system you should be able to remove these nutrients with simple water exchanges.
 
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I just ordered the Sea Kleer .

I like the idea of acquiring my target quicker and with some control while maintaining levels with GFO.
I hope to master this as I haven't got my PO4 below .1 since moving tank.
I don't want to starve my fish and read a great article last night that along with Gregs advice and method gives me hope I will have my PO4 in control soon enough .
I read this article last night and am convinced between that info and this thread I should have no problem. Probably start next weekend.. I just saw Lanthium reactors...

Greg where do add the dose and how do you remove the flocculant ?
 
I think I mentioned it earlier, in case I didn’t;

I calculate how many drops of LC I need to lower P4 only 0.04ppm in my 500 gallon system, in any 48 hours (2 days) so if I need to lower 0.12ppm I do it over 6 days. This is ultra cautious to not freak the corals out.

Dropping P4 too fast and lack of focculant control is where it goes bad for people and their livestock.

I add the drops to 500ml of Ro water and add that to a feeding bag (IV bag) and drip the solution into the intake of my skimmer over about a hour. That is a treatment that will lower P4 by 0.04ppm each time it’s done. The gradual reaction happens slowly in the skimmer, where maximum mixing happens fast enough to produce focculant slowly enough that it is all grabbed by the skimmer.

Doing this very slowly has worked very well. It repeats exactly.

Disclaimer...this is the most effective and dangerous way to control Phosphates in a reef tank. But if precautions are taken I think you can vastly improve the safety. And good heavens it’s cheap.
 
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