How much PO4 is too much

[PSXerholic]

Easy......get Nitrates up a bit and ......... Google for Buddendorf ratio and follow the Redfield ratio.
Make sure your Nitrate and Phosphate readings are done with accurate test kits in the lower range you're in ;-)

-Andre

 

[Klwheat]

Algae growing on the glass is neither unusual nor a big concern. But it is brown and not green?

I discuss phosphate in detail here:

Phosphate in the Reef Aquarium

That's an awesome write up. The scientist in me greatly appreciates it! Thank you!

 

[skim]

If you have no outbreak of any nuisance algae what does it matter what your phosphate is, if everything is doing well. It is true if you would like to extend the time between scrapings you could just add some GFO and that should do it, but it is an added expense and scraping the glass is not that hard to do, and scraping of the glass does offer a food source for filter feeders and also your skimmer should skim it out.

 

[Kzoo]

From my understanding the high P04 will make corals expel there Zooxanthellae algae and over time will not regrow killing the coral.

 

[Fercho]

Easy......get Nitrates up a bit and ......... Google for Buddendorf ratio and follow the Redfield ratio.
Make sure your Nitrate and Phosphate readings are done with accurate test kits in the lower range you're in ;-)

-Andre

Yep, totally agree.
Read up on the redfield ratio.
Basically, nitrate levels should be more than phosphate levels.
The ratio is 6:1 or so.
6 being nitrates
1 being phosphates

Trust this. I have played with and witnessed this in my own tank. When you have this two levels right, it doesnt take long (between a month or two) to start seeing white tips on your corals, sign of coral growth.

 

[skim]

Boy oh Boy, what did we do when we had no Phosphate test kits.

 

[711reefer]

Boy oh Boy, what did we do when we had no Phosphate test kits.

we bought more snails. and when we had gha we bought a lawn mower blenny or a tang

 

[Vaughn17]

Yep, totally agree.
Read up on the redfield ratio.
Basically, nitrate levels should be more than phosphate levels.
The ratio is 6:1 or so.
6 being nitrates
1 being phosphates

Trust this. I have played with and witnessed this in my own tank. When you have this two levels right, it doesnt take long (between a month or two) to start seeing white tips on your corals, sign of coral growth.

Or so...LOL. The ratio was 16 to 1 but was recently revised to 14 to one.

 

[Randy Holmes-Farley Verified Community Expert]

That's an awesome write up. The scientist in me greatly appreciates it! Thank you!

Thanks.

Happy Reefing.

 

[Fercho]

Or so...LOL. The ratio was 16 to 1 but was recently revised to 14 to one.

Lol...
Oops, my bad...
At least i got the No3 more than Po4 part right...

 

[Randy Holmes-Farley Verified Community Expert]

Folks should bear in mind that these ratios have nothing to do with target levels in the water. They are uptake ratios, not somehow "desirable" ratios in the water.

 

[PSXerholic]

Randy is absolutely correct!!!
It is for non scientific people hard to understand what this really is about and how it actually truly works ;-)

For "normal" folks,
following the Redfield ratio or Buddy ratio just ensures your nutrients are balanced in a way that potential nuisance algae have a less desirable environment to thrive, hence less chance of algae issues.
This is based on the Liebig's law of minimum which you can apply to almost every form of life.......

I always had great success to keep my tank algae issue free, when applied this ratio for nutrients.
Todays problem is with low nutrient systems or worse, non detectable nutrients in many tanks, the fine tuning in these low ranges is not as easy to maintain without automatism, and even harder with smaller tank systems due to instability in small systems.

Here a graph covering the lower ranges a bit better.

Reference - Picture as Courtesy out of Andre's Reef Guide for Coral Colorization Part#1


-Andre

 

[PSXerholic]

Randy is absolutely correct!!!
It is for non scientific people hard to understand what this really is about and how it actually truly works ;-)

For "normal" folks,
following the Redfield ratio or Buddy ratio just ensures your nutrients are balanced in a way that potential nuisance algae have a less desirable environment to thrive, hence less chance of algae issues.
This is based on the Liebig's law of minimum which you can apply to almost every form of life.......

I always had great success to keep my tank algae issue free, when applied this ratio for nutrients.
Todays problem is with low nutrient systems or worse, non detectable nutrients in many tanks, the fine tuning in these low ranges is not as easy to maintain without automatism, and even harder with smaller tank systems due to instability in small systems.

Here a graph covering the lower ranges a bit better.

Reference - Picture as Courtesy out of Andre's Reef Guide for Coral Colorization Part#1


-Andre

As you can see, it is impossible to work with todays Hobbyists Test equipment accuracy in the range below 0.25ppm No3 ................. So here is where the art of nutrient control starts, in order to minimize algae.

I personally advise to stay in the 1-2ppm No3 range for ease of maintenance with decent Coral colors ;-)

-Andre

 

[Myka]

If I were you I would try getting some NO3 into the tank. If your tank is NO3 limited that could be causing the PO4 to rise too high. I find most SPS tanks looks best if there is some measurable NO3 (>0, <5 ppm) and some measurable PO4 (>0, <0.03 ppm). You're probably getting a false low reading though since there is active algae in the tank that are using some of the available NO3 and PO4. So there is more PO4 available than you tested, and certainly a small amount of NO3 as well.

 

[Joe Batt]

So looking at the chart above with reference to the Redfield ratio my tank has a steady No3 of 2 and a Po4 of 0.03. This would seem to say that my Po4 is too low? Should I increase it or am I just chasing rabbits down holes?

 

[Joe Batt]

When i get brown algae on the front glass i just ADD nitrate

I notice the algae on the glass is brown as opposed to green.

I dose NoPox and my No3 is a steady 2 and Po4 0.03. I also notice my corals are slow to grow compared to other peoples tanks and possibly with less colour.

I dose 24/7. Ca, Kh and Mg. My Ca is steady at 430 and Kh steady at 9.2dKh.

I use a RoDi system and check it regularly TDI is at 0.

My flow is good, around 35x volume and lighting is via Hydra 52 HD plus supplemental 2xT5. Photo-period is around 10 hours a day with the PAR at the top around 250 and at the bottom 175.

Weekly cleaning, and vacuuming the sand. Bi weekly 10% water changes.

Any tips as to where I might be going wrong? I put a lot of effort into my tank and have done for 2 years with not great results. The most annoying thing is I know friends who seem to do nothing to their tanks and have amazing growth and colour even though their levels are off when I have tested their water.

 

[dbrewsky]

I notice the algae on the glass is brown as opposed to green.

I dose NoPox and my No3 is a steady 2 and Po4 0.03. I also notice my corals are slow to grow compared to other peoples tanks and possibly with less colour.

I dose 24/7. Ca, Kh and Mg. My Ca is steady at 430 and Kh steady at 9.2dKh.

I use a RoDi system and check it regularly TDI is at 0.

My flow is good, around 35x volume and lighting is via Hydra 52 HD plus supplemental 2xT5. Photo-period is around 10 hours a day with the PAR at the top around 250 and at the bottom 175.

Weekly cleaning, and vacuuming the sand. Bi weekly 10% water changes.

Any tips as to where I might be going wrong? I put a lot of effort into my tank and have done for 2 years with not great results. The most annoying thing is I know friends who seem to do nothing to their tanks and have amazing growth and colour even though their levels are off when I have tested their water.

Whats your bioload? What and how often are you feeding? When is the last time you changed ro filters/di resin?

 

[dmw913]

Good morning, friends! I'm having an exceptionally similar issue to @Reefpro with the brown film on the glass, undetectable NO3 and elevated phosphate. Both here and elsewhere folks have recommended actually raising NO3 levels which makes sense. However, I have added a fish and increased feeding with no real resulting increase in NO3 and I'm wary of this continued practice given that the increased feeding is going to also increase phosphate over time if my understanding is correct. I have also thought about taking most/all of my chaeto out of my reactor to help drive levels.

So, to those who have discussed raising NO3 with additives, what would you use? I have read that some folks use Spectracide and I have to be honest, the idea of putting things I get at Home Depot in my tank makes me almost wet my pants. Other suggestions for additives that I might be able to mentally stomach?

 

[Joe Batt]

Whats your bioload? What and how often are you feeding? When is the last time you changed ro filters/di resin?

A 350 Reefer with 8 fish, all reasonable sizes, from 2-6 inches. I feed them 1 cube of defrosted strained mysis in the morning and good pinch of dried food in the evening. I also put some seaweed in the tank once a day on a clip. I also feed the corals 3-4 times a week with 5ml of Reef Energy A&B and a couple of times a month with Reef Roids.

The RO filters were changed about 6 weeks back and the Di resin about the same time. Its giving TDI of 0, also a colour changing resin and still blue .

 

[Randy Holmes-Farley Verified Community Expert]

So, to those who have discussed raising NO3 with additives, what would you use? I have read that some folks use Spectracide and I have to be honest, the idea of putting things I get at Home Depot in my tank makes me almost wet my pants. Other suggestions for additives that I might be able to mentally stomach?

It is easy to buy food grade additives online.

http://etsy.me/2uucVPf