Should I add phosphate to help lower my nitrates?

The API phosphate Test measures phosphates at top high of a range. You need a test set that measures phosphates at lower increments.
 
I concur with earlier post's in the thread please consult vodka dosing experts to see my opinion on a safe vodka dosing/Dr. Tim's wasteaway routine.
 
It will take a while if PO4 is indeed the limiting nutrient. I was adding 2 PPM at one point b/c i had dinos and other things consuming it down to sub .02 in two days.
 
Seem like the same results as the past few days. Added 0.50mg/L today. That was all I had left of the seachem bottle, so hopefully some better results tomorrow. I have noticed the algae in the refugium is getting much greener! Hopefully that is a good sign that this is working. I think I’ll do a 25% water change and give it a week to rest as I’ll be out of town. Don’t want to bother the tank sitter with to much.

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Seem like the same results as the past few days. Added 0.50mg/L today. That was all I had left of the seachem bottle, so hopefully some better results tomorrow. I have noticed the algae in the refugium is getting much greener! Hopefully that is a good sign that this is working. I think I’ll do a 25% water change and give it a week to rest as I’ll be out of town. Don’t want to bother the tank sitter with to much.

B6FC3637-D536-4C3D-9CF2-05AB3487751C.jpeg
a big water change or two will help a lot!
 
Sorry I was on vacation then I was sick from vacation! I did a 50 gallon water change on the 17th.
 
These were the results last night. I added around 1ppm phosphate of a hydroponics fertilizer I got on amazon. It is super potent so a little goes a long way unlike the seachem. The instructions say 2/3 teaspoon will raise phosphate 50ppm in 10 gallons! I will post the test results later on today after I test again tonight. I did get a Hanna checker on Black Friday, so I will be breaking it out tonight also!

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Tank that size I would convert to Zeovit or Aquaforest ULNS. Just my 2Cents...solve those issues for good.
 
Tank that size I would convert to Zeovit or Aquaforest ULNS. Just my 2Cents...solve those issues for good.

By giving up and paying someone else to solve it with potions of unknown content? :D
 
So these are the results tonight. I’m not adding anything tonight. I will see what results I get tomorrow.

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Tonight it looks like the phosphate is down a little. I used the api kit tonight because the Hanna only came with 6 test. I don’t want to use them all up right away. I will recheck it next week or when the api kit is unreadable. Not adding any phosphate tonight. I want to see how fast it will consume the 1ppm phosphate.

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What's your chaeto growth look like? Are you still dosing a carbon source? My nitrates dropped in correlation with chaeto growth (which exploded) and po4 b/c of dinos. If you don't have either consuming a ton, it could still take a while. I agree to wait for the po4 to drop and see if nitrates come with it. Also, you should have got the Hanna ULR but that would should be good enough to tell PO4 isn't too low.
 
What's your chaeto growth look like? Are you still dosing a carbon source? My nitrates dropped in correlation with chaeto growth (which exploded) and po4 b/c of dinos. If you don't have either consuming a ton, it could still take a while. I agree to wait for the po4 to drop and see if nitrates come with it. Also, you should have got the Hanna ULR but that would should be good enough to tell PO4 isn't too low.
Before I started dosing PO4 the cheato was dying off. It was a very pale green, and went from a couple softball sized chunks to about a golf ball size piece. Since adding the po4 it has turned a much darker green and the sump has a lot of green algae growing on the rocks and glass. The chato is still almost the same size, but I’m assuming that small a piece will take time to regain size. I still have my biopellet running, but I’m not dosing any other carbon sources.
 
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@AbsoluteZer0273 Are you N's and P's high enough to support carbon dosing (pellets) and a chaeto bundle? Each one is going to need/use large amounts of nitrates....potentially large amounts of P as well.
 
@AbsoluteZer0273 Are you N's and P's high enough to support carbon dosing (pellets) and a chaeto bundle? Each one is going to need/use large amounts of nitrates....potentially large amounts of P as well.
I think my nitrate can support both. They have never been under 60ppm, however my PO4 has been very low the whole time. Always unreadable with the api kit. This is why I’m trying the addition of PO4 to see if the Redfield ratio is playing a part in my extreme nitrates. I have a little over a liter of pellets that have been running several months now with little decrease in nitrates. Ideally I would like to just have a large refugium and not have to carbon dose, but I have been told a million different things to use to “lower” my nitrates that haven’t worked. I only leave the biopellet reactor online because I don’t want to lose a large part of my beneficial bacteria. I’m hoping to see some positive results from dosing po4 this weekend. Then I can hopefully be on my way to a stable reef chemistry!
 
You are on the right track then, but that's nutrient limitation at work.....not the redfield ratio.

Organisms that can't use P at the levels or forms available, then they will be unable to grow, repair and/or reproduce.

This includes the bacteria in your tank...including those ones you hope will populate the bio-pellets and process your nitrates faster.

It sounds like you may be chasing the "low nutriet" concept...if so I'd suggest caution.

I would dose PO4 to eliminate a potential nutrient bottleneck, but personally I would not run the bio-pellets. Your NO3 numbers aren't necessarily a problem.
 

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