Phosphorus question

[Billyjack]

Looking for advice on best way to deal with excess phosphorus..the excess phosphorus is from the city water..there are several local reefers with the same issue...Thanks

 

[Randy Holmes-Farley Verified Community Expert]

Are you using an RO/DI? That should be adequate.

 

[Billyjack]

Yes I am..the city water report says that phosphorus is 63 ppb in the water source and can’t get tank water under 30..are there certain filters that help with phosphorus?

 

[ataller]

Yes I am..the city water report says that phosphorus is 63 ppb in the water source and can’t get tank water under 30..are there certain filters that help with phosphorus?

Like Randy said, an RO/DI will give you water with 0 phosphorus.

 

[Billyjack]

Ok I have a brs ro/di with 1 sediment 2 carbon 1 ro membrane and 1 di chamber..which filter would remove the phosphorus?

 

[dwest]

Ok I have a brs ro/di with 1 sediment 2 carbon 1 ro membrane and 1 di chamber..which filter would remove the phosphorus?

Ro membrane

 

[reeferfoxx]

Ok I have a brs ro/di with 1 sediment 2 carbon 1 ro membrane and 1 di chamber..which filter would remove the phosphorus?

Membrane. But are you testing phosphorus in the tank or the rodi water?

 

[Billyjack]

Testing tank water..but I could get a new membrane or try a dual ro membrane

 

[reeferfoxx]

Testing tank water..but I could get a new membrane or try a dual ro membrane

Ok, so if you test the rodi water and it shows zero phosphorus, then why upgrade the rodi when all you need to do is limit food going into the tank?

 

[Billyjack]

I haven’t tested the top off water yet

 

[reeferfoxx]

I haven’t tested the top off water yet

Well, in case you don't understand, phosphorus/phosphates typically comes from excess or decaying food. Nitrates come from nitrifying bacteria that would convert fish urin and decaying food(ammonia source) into nitrates. Now, if you have phosphorus/phosphates but don't have a nitrate reading, then you are nitrate limited. Most organisms in our reefs consume both N and P at different rates. However, those same organisms, like bacteria, need both to consume. Sort of like a tetter totter. So, if you are nitrate limited you need to figure out a way to add more nitrates without adding phosphate. You can do this by dosing nitrates or adding more fish.

 

[Randy Holmes-Farley Verified Community Expert]

Yes, unless you use raw tap water, foods are the source, and whether they are eaten or just rot in the bottom doesn’t matter.

 

[Billyjack]

I have 0 phosphates and 42 ppb on phosphorus