Phosphate

[STEVE]

What would cause your phos to be a 0.18? I run cheato, do regular water changes... I feed with PE Mysis, Rods, and pelletts. Could it be the pellets, Dainichi Marine Reef Veggie FX? I just thought my cheato would take care of the phosphates, am I thinking wrong? Should I be running GFO aswel? I thought if I ran both, the cheato would die off???

[Guest]

Have you tested your RODI water?

[STEVE]

Do you test your ro/di with the same Hanna Checker? or is there another FRESH water test kit to use?

[STEVE]

ro/di was 0.05, just out of curosity I checked the tap water....1.07. So if my tank is 0.18, it must be something I am putting in the tank, like food...???

[Matt LeBaron]

How old is the live rock/substrate in your tank?

 

I had some odd algae growth for a little while, even though my Phosphate was reading low. Just couldn't figure it out until I noticed that some new rock I added to the tank didn't have any of the hair algae growing on it. It then occured to me that the LR I have was the same stuff I used several years ago when I was running a much "dirtier" setup with a bunch of macro and no corals. Realized that with my new setup being much cleaner due to keeping corals that the LR was likely leeching Phosphate back into the water since it was so low in the water column now.

 

I added a reactor with some GFO (about half what is actually recommended for a tank my size) and the hair algae has been slowly disappearing over the course of about 2-3 weeks without changing anything else and I'm actually feeding a bit more. Not sure how long before the LR leeches out all of the Phosphate it has been holding but I figure I'll just keep running a little bit of GFO.

[STEVE]

Thanks Matt...My rock is about a year and a half old. What does your ro/di straight out of the hose read as far as Phosphate? Mine was like0.05. I'm actually going to test my made up salt water now...

[STEVE]

My made up salt mix (still at 1.020) is 0.05. My ro/di was 0.05... so I dont think the Reef Crystals are adding any phos.

[zygote2k]

You say your rock is a year and a half old but on your build thread you say it's brand new eco-rock from BRS. This is starting to sound like Scott's (MBVet) issue all over again and he used the same rock.

 

Here's my whole take on phosphate in reef tanks.

When you set up a tank and its totally barren of life, you have to let the life happen naturally. When enough bacteria colonizes the rock, the nitrate, nitrite, ammonia can no longer be detected. When you let the algal cycle run its' course, the P04 will no longer be detected. Anything you do to hamper this process (adding GFO) will cause you to have detectable amounts of phosphate. If you're patient, and all things are stable (r/o, food sources, etc), then you can watch the growth of hair algae actually lower the amounts of detectable phosphate in the water. Hopefully you'll have a decent sized fuge in which to grow macroalgae, so you don't have to worry about hair algae. Growing either of these algaes, then harvesting them on a periodic basis will keep the phosphate in check.

[STEVE]

Im not talking about the 300 new build......my 90, sorry.

[STEVE]

The 90 is well established...with a fuge and cheato that I harvest regularly. Im trying to find the source of p04.

[Guest]

I don't think RODI water should read any phos. That could be the issue. Make sure to change filters annually. I would also try another brand of test kits like Red Sea or Salifert. Adding bacteria like probio and dosing VGV or using Biopellets should help. Also could add a Phosphate reactor?

[sen5241b]

One simple thing causing high phospates that people overlook is overstocking.

[BaySailor]

Run gfo and test. I'd worry less about your Cheato and more about the algae problems you'll get w/too much PO.

[Decadence]

What is your nitrate reading? You may have reached a point of limitation from low nitrate levels which would allow your phosphate to rise. When phosphate is consistently high for any length of time, it saturates your rock and sand. It takes weeks-months for the bacteria to remove all of the phosphate from the calcium carbonate in your tank so often times, people will jump-start this process by replacing the entire sand bed with new, dry sand. I would definitely run GFO on the tank. Phosphate is more harmful than nitrate and your tank processes nitrate naturally while phosphate levels are allowed to simply build. Water changes do not remove much phosphate from the equation because the binding process will not allow you to remove what is in the system, only in the water column at that particular time.

 

I run an algae turf scrubber, large protein skimmer and GFO to keep the heavy bio-load that I do and still keep water quality high enough for SPS. The algae scrubber readily converts inorganic phosphate and nitrate into organic matter which can be removed by hand or skimmed if it were to fall from the ATS and become available in the water column. Most inorganic nutrients are hydrophobic (not attracted to the oxygen via charge) and cannot be skimmed while the organic matter is hydrophilic and can be skimmed. I feel that these two methods of nutrient reduction complement each other very well. My reasoning for running GFO (and I only run half of what is recommended) is to tip the scaled in the favor of phosphate limitation rather than nitrate limitation.

 

I do change water from time to time but only to replace trace elements. Phosphate levels are consistently below 0.015 and nitrate is naturally handled by my rock and stays bellow 1ppm so I use my old display water to do water changes in my filterless mantis tank.