High nitrates and phosphates, but no nuisance algae

[SeaDweller]

So a slightly older salifert PO4 test kit showed my DT with 0.3 (or 0.03) phosphates but a brand new kit shows a blue darker than 3 on the color scale. My NO3 is 100 (or more), but I don't have algae issues at all.

This was an SPS dominant tank that has fallen over the course of two years, but I'm turning it around. Got a sulfur reactor running to lower NO3 and just threw GFO on last night, but how could I have that high of nutrients and not have a nuisance algae issue? Yes I have tangs and stuff, but the only algae I get is the brown film stuff on the tank.

If my PO4 is this high, is it safe to assume my gfo will be exhausted within a day or less? It's 240 gallons and BRS calculates I need 3.75 cups of it, but I can only fit so much in their reactor.

 

[EmdeReef]

I would first check the test kits. Assuming they're accurate, it can happen. There are some very successful reefers who run high phosphates and don’t have algae issues e.g. @Thales. If I had to guess, something is outcompeting algae in your tank but without further investigation would be difficult to say what.

As for getting the phosphates down I would go the lanthanum route. You’d go through a lot of GfO to make a dent there.

 

[SeaDweller]

I would first check the test kits. Assuming they're accurate, it can happen. There are some very successful reefers who run high phosphates and don’t have algae issues e.g. @Thales. If I had to guess, something is outcompeting algae in your tank but without further investigation would be difficult to say what.

As for getting the phosphates down I would go the lanthanum route. You’d go through a lot of GfO to make a dent there.

I've noticed a decline or stop or lack of coralline growth. I have some nuisance palys and some nems and what used to be some GSP before I recently treated the tank with fenbendazole to kill it. I'm trying to get the tank ready for acros again, other than that I have a bunch of tangs and a handful of smaller fish.

I've looked into the LC, and will test again today.

 

[Thales]

There are plenty of tanks that show low nutrients and have algae problems and plenty of tanks that show high nutrients but don't have algae problems. In not brand new tanks, I think herbivores (including you) are the right answer to algae problems, not nutrient control.

There can be bounce back issues from LC and GFO, so watch for that by testing the tank water and the GFO effluent and seeing the difference.

I have an article in Reefs Magazine about this issue if you are interested. I think it is called 'Test kits, chasing numbers, and phosphate'.

 

[wattson]

its good a thing

 

[SeaDweller]

its good a thing

Agreed, but not when I'm trying to go full blown acros again

 

[revilo88]

I have had 0.9 phosphate and 50 Nitrate before with no nuisance algae.

Could not grow any Chaeto either, even after doing Iron.

My tank is weird....

 

[SeaDweller]

I have had 0.9 phosphate and 50 Nitrate before with no nuisance algae.

Could not grow any Chaeto either, even after doing Iron.

My tank is weird....

It's crazy huh?

After about 1.5 of gfo my effluent is reading 1.0 ppm and the tank is clearly between 1 and 3 on the salifert test. I'll be content at 0.1 or slightly less for my tank for my planned corals.

 

[Randy Holmes-Farley]

I have had 0.9 phosphate and 50 Nitrate before with no nuisance algae.

Could not grow any Chaeto either, even after doing Iron.

My tank is weird....

Probably limited in some other trace element.

 

[Randy Holmes-Farley]

It's crazy huh?

After about 1.5 of gfo my effluent is reading 1.0 ppm and the tank is clearly between 1 and 3 on the salifert test. I'll be content at 0.1 or slightly less for my tank for my planned corals.

Not crazy, just complicated.

Politics, that's crazy

 

[SeaDweller]

Not crazy, just complicated.

Politics, that's crazy

That's an understatement!