Phosphate testing 0

stevenVDB

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Been struggling for a month with fluctuating and high phosphates 0.18-0.26.

Today I bought a new lot of Hanna reagent and the conclusion is that I’ve been using a bad lot for a month.

In stead of my phosphates are at 0.19 today they are actually at 0.00. Tested today with a bad lot and a new one.

Any advise on how I can slowly increase my phosphates.
 

maxs

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What’s your salinity? I found if my salinity is off then everything is off. Assuming your salinity is in normal range I would consider neophos from brightwell aquatics
 

EnterName

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Been struggling for a month with fluctuating and high phosphates 0.18-0.26.

Today I bought a new lot of Hanna reagent and the conclusion is that I’ve been using a bad lot for a month.

In stead of my phosphates are at 0.19 today they are actually at 0.00. Tested today with a bad lot and a new one.

Any advise on how I can slowly increase my phosphates.
I would try another test kit just to make sure and replace the batteries of the HannaChecker even if it doesn't display the low battery warning yet.

If you actually need to add phosphate you can use monosodium phosphate:


I dose phosphate daily using dosing pumps and can only advice you to test daily when dosing until you are absolutely sure that phosphate doesn't keep accumulating. In the beginning, substrate and rock might bind a lot of phosphate, but once the equilibrium between dissolved and bound phosphate shifts, dosing will have a larger effect and you might overshoot.
 
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EnterName

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What’s your salinity? I found if my salinity is off then everything is off. Assuming your salinity is in normal range I would consider neophos from brightwell aquatics
Salinity is fine ar 35. Tank is 5 months old
Did you start with lots of dry rock or dry sand by any chance? Those can take quite a long time to saturate sufficiently until the equilibrium between dissolved and bound phosphate allows for detectable phosphate levels.

If you are still going through the ugly phase or experience some other type of algae growth, it's also possible that the phosphate consumption is very high.
 
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stevenVDB

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Did you start with lots of dry rock or dry sand by any chance? Those can take quite a long time to saturate sufficiently until the equilibrium between dissolved and bound phosphate allows for detectable phosphate levels.

If you are still going through the ugly phase or experience some other type of algae growth, it's also possible that the phosphate consumption is very high.
When I started the tank I used the mature rock from my previous tank. 2 weeks after added some new dry rock. ( a week later I saw massive swings in the parameters, due to the new dry rock)

End of last month I added again some new dry rock. But this time I matured it in a separate container for 2 months.
 

EnterName

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Did you start with lots of dry rock or dry sand by any chance? Those can take quite a long time to saturate sufficiently until the equilibrium between dissolved and bound phosphate allows for detectable phosphate levels.

If you are still going through the ugly phase or experience some other type of algae growth, it's also possible that the phosphate consumption is very high.
When I started the tank I used the mature rock from my previous tank. 2 weeks after added some new dry rock. ( a week later I saw massive swings in the parameters, due to the new dry rock)

End of last month I added again some new dry rock. But this time I matured it in a separate container for 2 months.
If this separate container didn't have much phosphate or the pH dropped too far there might not have been much calcium phosphate precipitation.

It's not an issue though, you can add a DIY monosodium phosphate solution (see link I posted previously), or get some product like Brightwell NēoPhos, Nyos Phosphate+, AquaForest PO₄ Boost, or whatever is available to you 😊

I recommend having a HannaChecker ULR Phosphate or Phosphorus available and keep measuring frequently.
 
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stevenVDB

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If this separate container didn't have much phosphate or the pH dropped too far there might not have been much calcium phosphate precipitation.

It's not an issue though, you can add a DIY monosodium phosphate solution (see link I posted previously), or get some product like Brightwell NēoPhos, Nyos Phosphate+, AquaForest PO₄ Boost, or whatever is available to you 😊

I recommend having a HannaChecker ULR Phosphate or Phosphorus available and keep measuring frequently.
Thank mate.

I’ve been using the hanne ULR on a daily base last month. That’s why I didn’t understand those daily differences in values.

There were phosphates in te container, I tested it weekly. When I transferred it to the tank it had .08 PO4 in the container.

I’ll order some po4+ today.
 
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EnterName

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If this separate container didn't have much phosphate or the pH dropped too far there might not have been much calcium phosphate precipitation.

It's not an issue though, you can add a DIY monosodium phosphate solution (see link I posted previously), or get some product like Brightwell NēoPhos, Nyos Phosphate+, AquaForest PO₄ Boost, or whatever is available to you 😊

I recommend having a HannaChecker ULR Phosphate or Phosphorus available and keep measuring frequently.
Thank mate.

I’ve been using the hanne ULR on a daily base last month. That’s why I didn’t understand those daily differences in values.

I’ll order some po4+ today.
Happy to help 🙂

Did you try measuring phosphate every day at the same time?

I could imagine phosphate levels being quite dependent on the feeding schedule, calcium/alkalinity dosing, and maybe even lighting schedule which affects pH and therefore probably the bound/dissolved phosphate equilibrium. Having a fixed 24/48/72 hour interval between measurements could reduce this perceived instability.
 
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stevenVDB

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Happy to help 🙂

Did you try measuring phosphate every day at the same time?

I could imagine phosphate levels being quite dependent on the feeding schedule, calcium/alkalinity dosing, and maybe even lighting schedule which affects pH and therefore probably the bound/dissolved phosphate equilibrium. Having a fixed 24/48/72 hour interval between measurements could reduce this perceived instability.
I do it daily same time before feeding.
 

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