High phosphate dilemma - help needed

[Idech]

I have very elevated phosphate and elevated nitrates. Phosphate is above 1.2 ppm and nitrates are above 45 ppm.

I started dosing vodka slowly a week ago (0.8 ml per day now) but it’s going to take forever to reduce phosphates to desired level (around 0.1). Corals aren’t growing and there is practically no alkalinity consumption in the tank (alk has been around 8.5-8.7 for more than 10 days).

I do 2 automatic water changes per day but they are too small to do anything (4L per day). Tank is 135 gallons (511 liters). I changed over 30 gallons a months ago.

I got rid of the Dino’s that were afflicting my tank for the last 5 years, on and off but mostly on. They have been gone for about 40 days now. Among other tools, I induced a diatom bloom and I don’t want to get rid of it. I need silicate to stay in the tank.

My question : how do I reduce phosphate efficiently without stripping the silicate in the tank (for fear of Dino’s reappearing) ?

Every solution I read about was either going to strip the silicate or posed a risk to my fish. I have dosing pumps and a media reactor if they are needed but I need to have a plan.

Thank you for your help !

 

[GHOSTLY]

I had my phosphate at .8 in my acro tank and it was horrible since my nitrate was low. Carbon dosing does very little on phosphate I notice. I had to address my route cause which was used live rock leaching nutrients back out. To combat it I did a series of ½ doses of phosguard in order to minimize shock and rapid depletion, causing dinos. Low silicates caused diatoms for me. Gfo would be good long run to maintain

 

[Idech]

I had my phosphate at .8 in my acro tank and it was horrible since my nitrate was low. Carbon dosing does very little on phosphate I notice. I had to address my route cause which was used live rock leaching nutrients back out. To combat it I did a series of ½ doses of phosguard in order to minimize shock and rapid depletion, causing dinos. Low silicates caused diatoms for me. Gfo would be good long run to maintain

The problem is GFO will strip silicates and Phosguard will remove them too, to a certain extent.

 

[GHOSTLY]

The problem is GFO will strip silicates and Phosguard will remove them too, to a certain extent.

Thats why I opted for ½ doses, feeding less, skimming more, and carbon dosing. It gives it a "break" to rise again. I do also use vancouver tap water for all my tanks so it may be possible that I supplemented silicates without knowing

 

[Randy Holmes-Farley]

I’m not certain you will see a big apparent benefit from lowering phosphate, but if you do not have tangs, then lanthanum is a possibility. I am not sure whether that too might bind some silicate, but maybe less than GFO or aluminum oxide.

 

[Idech]

Thats why I opted for ½ doses, feeding less, skimming more, and carbon dosing. It gives it a "break" to rise again. I do also use vancouver tap water for all my tanks so it may be possible that I supplemented silicates without knowing.

Curious flow what TDS is like in Vancouver water?

 

[Idech]

I’m not certain you will see a big apparent benefit from lowering phosphate, but if you do not have tangs, then lanthanum is a possibility. I am not sure whether that too might bind some silicate, but maybe less than GFO or aluminum oxide.

I do have a mature yellow tank from Hawaii and I wouldn’t want to risk it. Tell me, is the elevated phosphate not the cause of my tank not consuming any alkalinity ?

Am I right in wanting alk to be consumed so corals can grow ? What would you do if it were your tank ?

 

[Randy Holmes-Farley]

I would not risk my yellow tang either.

Can you post a picture of the tank?

 

[BryanM]

I do have a mature yellow tank from Hawaii and I wouldn’t want to risk it. Tell me, is the elevated phosphate not the cause of my tank not consuming any alkalinity ?

Am I right in wanting alk to be consumed so corals can grow ? What would you do if it were your tank ?

It could be.

Right now since you have a tang I would run GFO in a reactor. It isn't cheap, but it does work, at least it worked well for me.

My target range is .1-.3.

Testing fairly often, you're likely to see it go down, and right back up to 1.2 for several go-rounds, but eventually it will go down and stay down(er).

AT that point you'll need a longer term strategy for keeping it down. Mine is an over-sized algae turf scrubber, but there's many options.

 

[GHOSTLY]

Curious flow what TDS is like in Vancouver water?

Its below 10. My tap is around 4-6 and my outside hose is the same. Some areas may be lower or higher but vancouver water is super clean. Little bit of seachem prime is all I use

 

[Randy Holmes-Farley]

Its below 10. My tap is around 4-6 and my outside hose is the same. Some areas may be lower or higher but vancouver water is super clean. Little bit of seachem prime is all I use

If you have copper pipes, there’s a risk from that. If you continue to use it, be sure to flush out your home pipes by running the water for a bit before collecting any.,

 

[Pistondog]

I have very elevated phosphate and elevated nitrates. Phosphate is above 1.2 ppm and nitrates are above 45 ppm.

I started dosing vodka slowly a week ago (0.8 ml per day now) but it’s going to take forever to reduce phosphates to desired level (around 0.1). Corals aren’t growing and there is practically no alkalinity consumption in the tank (alk has been around 8.5-8.7 for more than 10 days).

I do 2 automatic water changes per day but they are too small to do anything (4L per day). Tank is 135 gallons (511 liters). I changed over 30 gallons a months ago.

I got rid of the Dino’s that were afflicting my tank for the last 5 years, on and off but mostly on. They have been gone for about 40 days now. Among other tools, I induced a diatom bloom and I don’t want to get rid of it. I need silicate to stay in the tank.

My question : how do I reduce phosphate efficiently without stripping the silicate in the tank (for fear of Dino’s reappearing) ?

Every solution I read about was either going to strip the silicate or posed a risk to my fish. I have dosing pumps and a media reactor if they are needed but I need to have a plan.

Thank you for your help !

Lanthanum is your most cost effective method.
Can you rehome the tang while you dose it?
Otherwise some gfo will help, but cost more and take longer.
As others have said, phosphates at that level are not likely your issue.

 

[Idech]

Can you post a picture of the tank?

This is it about 14 months ago, because I fought Dino’s and lost most of my corals.

Right now since you have a tang I would run GFO in a reactor. It isn't cheap, but it does work, at least it worked well for me.

GFO will strip my silicate and Dino’s will come back.

Can you rehome the tang while you dose it?

I wouldn’t want to stress it so much. It gets nervous when I approach the tank.

Otherwise some gfo will help, but cost more and take longer.

Not really an option, as mentioned, it will make my diatoms disappear and they are needed against Dino’s.

As others have said, phosphates at that level are not likely your issue.

What could be my problem then ? Isn’t high phosphate stopping coral calcification ?

 

[Randy Holmes-Farley]

The coralline is likely the biggest alk user there. That can use a lot, but if it is not rapidly growing for any reason, alk demand may be low.

It’s a fine plan to reduce phosphate and see if alk demand picks up, but the soft corals are a low to no user of alk.

 

[Idech]

The coralline is likely the biggest alk user there. That can use a lot, but if it is not rapidly growing for any reason, alk demand may be low.

It’s a fine plan to reduce phosphate and see if alk demand picks up, but the soft corals are a low to no user of alk.

There isn’t much coralline left unfortunately. Mostly diatoms and hard green algae (green coralline) but not nearly as much. I added 5 hammers a few weeks ago.

Is Bacto energy a good choice in my situation (1.4 ppm phosphate and 45 ppm nitrates and not remove silicates) ?

 

[GHOSTLY]

If you have copper pipes, there’s a risk from that. If you continue to use it, be sure to flush out your home pipes by running the water for a bit before collecting any.,

I actually had this concern and was wondering something about it. Does using seachem prime really "detoxify" and make water 100+ safe?

 

[Randy Holmes-Farley]

I actually had this concern and was wondering something about it. Does using seachem prime really "detoxify" and make water 100+ safe?

There is no reason to think so.

 

[Randy Holmes-Farley]

There isn’t much coralline left unfortunately. Mostly diatoms and hard green algae (green coralline) but not nearly as much. I added 5 hammers a few weeks ago.

Is Bacto energy a good choice in my situation (1.4 ppm phosphate and 45 ppm nitrates and not remove silicates) ?

Organic carbon dosing typically does a good job on nitrate and a poor job on phosphate for well understood reasons:

1. The amount of phosphate available and needed to be removed to reduce it can be far, far higher than testing shows due to a lot of it temporarily attached to rock and sand

2. Denitrification, a process that is driven by organics, consumes nitrate and not phosphate

 

[Idech]

Organic carbon dosing typically does a good job on nitrate and a poor job on phosphate for well understood reasons:

1. The amount of phosphate available and needed to be removed to reduce it can be far, far higher than testing shows due to a lot of it temporarily attached to rock and sand

2. Denitrification, a process that is driven by organics, consumes nitrate and not phosphate

Okay. I’ll use Bacto energy mostly for nitrates. What do you suggest for phosphate, without stripping the silicate ?

 

[Randy Holmes-Farley]

Okay. I’ll use Bacto energy mostly for nitrates. What do you suggest for phosphate, without stripping the silicate ?

I think the easiest way is to just dose silicate while using a binder, but growing macroalgae or an ATS will use little to no silicate.

The amount of silicate loss using lanthanum is unknown, but there is a slight risk to tangs.