How fast is too fast to drop PO4?

[BrettMallette]

Just before Christmas i realized something was going on with my 55G tank. Hair algae had exploded everywhere. So grabbed my crappy api test kit to see what phosphates and nitrates were. Nitrates came up as 10ppm which ive never rly paid attention to so didnt do a check with anything else. Checked the PO4 and the api test came out as deep purple which equated to over 10ppm. Grabbed my hanna ULR phosphorous checker and kept diluting tests until it would read and low and behold phosphate was at over 10ppm. Which i equate to extremely heavy handed feeding by my roommates while i was out of town. Have since lowered it over the past 3 weeks to .956ppm. Things have gone thru phases of happy and ticked over those 3 weeks which i equate to when the GFO is at capacity.

So the question is... How fast is too fast to lower PO4 and what should I be aiming for?

Tank specs:
Salinity 1.025(refractometer)
Alk 8.8-9 (Hanna Checker)
Cal 420 (Red Sea Ca Test)
Mag 1300 (Salifert Mag Test)
PO4 .956ppm 312ppb (Hanna ULR Phosphorous)
Salt IO Reef Crystals
Lights 2×Hydra 26HD

 

[BryanM]

If its bound to rocks and sand... Likely... you're in for a long haul to get it down and to stay down.

I'd aim for .2-.3 a day with whatever method you choose. I've read as much as .5 a day is okay, but that seems like a lot.

 

[Randy Holmes-Farley]

Slower is much better than faster. Many more people report that problems start when they tried to lower phosphate than have actual coral problems at the higher phosphate.

I’d limit binding to 0.05 ppm or less per day.

 

[BrettMallette]

Slower is much better than faster. Many more people report that problems start when they tried to lower phosphate than have actual coral problems at the higher phosphate.

I’d limit binding to 0.05 ppm or less per day.

So i would be better off to use GFO in a high flow area in filter bag rather than a reactor then correct? Was using Rowaphos in a reactor and it seemed to be dropping wayy too fast and depleting too fast. Was only using the minimum in my two little fishies reactor, so about 4 tablespoons to get me the 2 inches of media. Currently running 2 tablespoons in a filter bag in a dedicated canister filter with only the GFO in it. I do not run a sump so putting it in filter socks or baffles isnt really an option.

 

[Randy Holmes-Farley]

The problem with a bag is most will not get used. If you kneed it around every day, that could work.

 

[BrettMallette]

Update.
Have PO4 down to 0.7665 ppm from when i last posted. 20% tank water with 80% fresh SW tested using the Hanna ULR phosporous checker. Have been using 3 tablespoons of rowaphos in a filter bag sandwiched between 2 layers of foam pad this seems to be working so far. Have been kneeding the bag every other day and it has been exhausting about every 7 days or so(phosphates start to rise up again)

Only corals that have taken poorly to the drop so far are cyphastrea.

 

[bakbay]

I've stopped using GFO ~8 years ago since I've discovered PhosphateRx (lanthanum chloride) to safely, effectively, and controllably reduce PO4. This stuff works extremely fast and effective so -- read the instructions! You should not reduce more than 0.5ppm/24 hrs. My PO4 was at 1.14 and I've dropped it down to 0.32 in a few weeks. PhosphateRx is super easy to dose -- 6 drops for every 10gal. I've been doing this across all my tanks for years w/o any issues; although I've heard of several horror stories (urban legends) with dying Hawaiian yellow tangs. I have them in all my tanks and no issues so far!

Phosphate Rx

Phosphate Rx is an amazingly simple and effective product that has revolutionized the way phosphates are removed from saltwater and freshwater aquariums. When added, the lanthanum-chloride formula rapidly binds to phosphate molecules making them inactive and easily filtered out. Regular use of...

www.bulkreefsupply.com

How to Use
Note: Do not dose directly in the display tank.Test your aquarium’s phosphate levels prior to use. Do not lower phosphates more than .5ppm in a 24-hour period.

• Add six drops of Phosphate Rx per 10 gallons of water. This will lower phosphates by approximately .5ppm. It is recommended to maintain phosphate levels below 0.03ppm.
• For best results, slowly place drops directly into your protein skimmer or into the overflow where the liquid and precipitate can be filtered through a 5 or 10 micron filter sock. Some temporary cloudiness may occur when adding this product. Cloudiness will clear within 24-hours.
• For accurate results, wait 24-hours before retesting your phosphate level. Wait ten minutes before dosing other supplements.
• Test regularly and treat as necessary.

 

[Randy Holmes-Farley]

. Do not lower phosphates more than .5ppm in a 24-hour period.

I would way, way reduce that amount. I'd drop less than 0.05 ppm per day. Fast drops cause more problems than high phosphate. Taking months is better than taking days.

Tangs are a risk with lanthanum, but it still can be an OK choice.

For folks wanting to use a known purity lanthanum DIY, here's a recipe:

DIY Lanthanum Dosing

Someone asked for a DIY lanthanum dosing recipe. Be sure you understand that some folks have issues with fish (especially tangs) before embarking on lanthanum dosing. it is also preferable to catch as many of the solids that precipitate out as you can, so dosing before some sort of...

www.reef2reef.com

This also has more on phosphate targets:

Randy’s Thoughts on Nutrient Target Ranges

Thoughts on Nutrient Target Ranges by Randy Holmes-Farley Almost nothing in the world of reef aquarium chemistry causes as much discussion as selecting and maintaining ranges for nitrate and phosphate. Some aquarists want low targets, some want...

www.reef2reef.com

 

[I never finish anythi]

I've stopped using GFO ~8 years ago since I've discovered PhosphateRx (lanthanum chloride) to safely, effectively, and controllably reduce PO4. This stuff works extremely fast and effective so -- read the instructions! You should not reduce more than 0.5ppm/24 hrs. My PO4 was at 1.14 and I've dropped it down to 0.32 in a few weeks. PhosphateRx is super easy to dose -- 6 drops for every 10gal. I've been doing this across all my tanks for years w/o any issues; although I've heard of several horror stories (urban legends) with dying Hawaiian yellow tangs. I have them in all my tanks and no issues so far!

Phosphate Rx

Phosphate Rx is an amazingly simple and effective product that has revolutionized the way phosphates are removed from saltwater and freshwater aquariums. When added, the lanthanum-chloride formula rapidly binds to phosphate molecules making them inactive and easily filtered out. Regular use of...

www.bulkreefsupply.com

How to Use
Note: Do not dose directly in the display tank.Test your aquarium’s phosphate levels prior to use. Do not lower phosphates more than .5ppm in a 24-hour period.

• Add six drops of Phosphate Rx per 10 gallons of water. This will lower phosphates by approximately .5ppm. It is recommended to maintain phosphate levels below 0.03ppm.
• For best results, slowly place drops directly into your protein skimmer or into the overflow where the liquid and precipitate can be filtered through a 5 or 10 micron filter sock. Some temporary cloudiness may occur when adding this product. Cloudiness will clear within 24-hours.
• For accurate results, wait 24-hours before retesting your phosphate level. Wait ten minutes before dosing other supplements.
• Test regularly and treat as necessary.

I second this . Been using phosphate Rx for about a year without any issues. I just use around 5 drops a week in to my reefmat in a 75g system

 

[BrettMallette]

I would way, way reduce that amount. I'd drop less than 0.05 ppm per day. Fast drops cause more problems than high phosphate. Taking months is better than taking days.

Tangs are a risk with lanthanum, but it still can be an OK choice.

For folks wanting to use a known purity lanthanum DIY, here's a recipe:

DIY Lanthanum Dosing

Someone asked for a DIY lanthanum dosing recipe. Be sure you understand that some folks have issues with fish (especially tangs) before embarking on lanthanum dosing. it is also preferable to catch as many of the solids that precipitate out as you can, so dosing before some sort of...

www.reef2reef.com

This also has more on phosphate targets:

Randy’s Thoughts on Nutrient Target Ranges

Thoughts on Nutrient Target Ranges by Randy Holmes-Farley Almost nothing in the world of reef aquarium chemistry causes as much discussion as selecting and maintaining ranges for nitrate and phosphate. Some aquarists want low targets, some want...

www.reef2reef.com

Have been going with your recommendations and things seem smooth so far. I have no intentions of doing LC i have experience with GFO so its easy on my brain. Dosing LC just doesnt seem safe when i dont want to even remotely risk my two fish as they are well over 2 decades old at this point.
Slow and steady wins the race on this one. According to my calculations ive been dropping 0.03ppm per day. Things are looking better every day and algae growth has completely stopped, while coralline has absolutely taken off.

 

[bakbay]

Have been going with your recommendations and things seem smooth so far. I have no intentions of doing LC i have experience with GFO so its easy on my brain. Dosing LC just doesnt seem safe when i dont want to even remotely risk my two fish as they are well over 2 decades old at this point.
Slow and steady wins the race on this one. According to my calculations ive been dropping 0.03ppm per day. Things are looking better every day and algae growth has completely stopped, while coralline has absolutely taken off.

Perhaps my math is grossly wrong but you've started with 10+ppm and now you're at 0.95 over 3 weeks. Isn't that closer to 0.5/day?

 

[BrettMallette]

Perhaps my math is grossly wrong but you've started with 10+ppm and now you're at 0.95 over 3 weeks. Isn't that closer to 0.5/day?

Sorry meant .03 after randy stated that it shouldnt be more than .05 per day. From 10+ to .952 was over 3 weeks. From Randys advice til now has been a week and its gone from .952 to .766

 

[rishma]

I posted this a while ago on how I used GFO to slowly lower phosphate, perhaps you’ll find it useful

GFO works and there is nothing innovative here, but perhaps this will be helpful to others. I previously struggled to get good results with GFO in small water volumes.

I keep a stable PO4 range around 0.08 ppm most of the time with carbon dosing (NP bacto), skimmer, and consistent food additions with an auto feeder. The balance took a while to find but it works well. My tank is only 100L. Occasionally when I get a new fish or get on a coral feeding kick, my phosphate jumps above my target range and doesn’t come back down so I take action to bring it back down with GFO. I’ve used the approach below many times and find it repeatable, so I thought I would share in case someone else finds it useful.


Here is my method to lower phosphates…


I add a small amount of GFO in a bag with carbon. For my 100L I use a tablespoon to start. I monitor daily or even 2x per day and then add another small bag of GFO when phosphate stops dropping. Rinse and repeat. I leave the original bag(s) in and just keep adding small bags (I don’t use a reactor).

In find that by adding small amounts I can keep a steady downward trend until I reach my target. Then I start removing the bags in reverse order every 2-3 days. This prevents the PO4 from changing quickly and prevents it from rising again after I reach my target. I figure that by going slowly I am removing larger amounts of total PO4 mass from tank, rather than smaller amounts from the water quickly which just get replenished through release from calcium carbonate surfaces.

The idea is that some of the PO4 is in the water and some (more?) is bound to the rocks and sand. By removing the PO4 slowly from the water, the corals don’t get stressed and PO4 is also slowly released from the calcium carbonate surfaces to get removed.

By removing one bag of GFO at a time, PO4 is still being removed, though more slowly by the bags that have older more saturated GFO. I usually only use 2 or 3 bags total, so it’s not complicated. After a couple days at the target PO4 I remove the last bag. The total process takes a week or two, but I don’t let phosphate get over about 0.25 ppm before I start the process. I keep the bags to use again in the future (in the same order).

I started this approach because I found GFO in larger amounts stripped the water too fast and PO4 would bottom out. The corals would react poorly. Then I would remove the GFO and PO4 would spike back up again. This YO-YO just stressed things out more. At one point I actually gave up GFO entirely for this little tank.

The unexpected effect was PO4 would stay in the target range after all the GFO was out and I was just back to carbon dosing.

Cheers