Add Nitrate to reduce Phosphates???

Discussion in 'Advanced Topics' started by Adam G, Jan 2, 2017.

  1. Adam G

    Adam G Born to Reef!
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    My 120g reef has issues. Getting RTN of my SPS and the only thing I can figure is phosphates. Alk has been rock steady at 9.2, Ca steady at 410ppm. Nitrates are undetectable on Red Sea test kit, and Phosphates were at .16. 2 water changes have it down to .12.

    I started running GFO in a reactor 2 weeks ago and it is not bringing phosphates down. With Nitrates undetectable my research is telling me to add some nitrates via KN03. The theory being the no nitrates is "starving" the nitrate and phosphate eating bacteria to a level where phosphates will no longer be reduced, nitrates are now the limiting factor.

    So.... my thought is no nitrates are no good anyway. Why not bump nitrates up to 2 ppm and see if this helps my phosphate problem.

    What do all you expert reefers think of this? Seem like a reasonable thing to try to get phosphates under control post haste to hopefully combat me watching my price SPS colonies go white in a matter of hours?
     
  2. jlanger

    jlanger "The North Remembers"
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    I'm not an expert, so don't expect any useful information from me. I'm working on my own nutrient issues.
    But...

    Do you know where your phosphates are coming from?
    Could your rock be leaching phosphates at a rate that your GFO reactor cannot keep up?

    I'll have to go look at your thread for more filtration information, as I cannot recall if you're implementing any carbon source for keeping your nutrient levels down. If you're using biopellets, vodka or other carbon dosing, it would make sense to add the nitrate to "feed" the bacteria.

    Sorry to hear about the corals. UGH!!!
     
  3. OP
    Adam G

    Adam G Born to Reef!
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    I don't think it is rock leaching. I used Carib sea life rock this time around and that is basically Carib Sea substrate in rock forms and then dyed. That was the whole purpose of using that stuff, no phosphate leaching. If something is leaching phosphate hopefully between GFO and bumping nitrates so bacteria can eat the phosphates might be a good combo to combat it maybe? Dunno, never had a problem with no nitrates, always the other way around!

    One thought for the source is if phosphates have been elevated for a while maybe the life rock has absorbed some and it will take a while to pull it all back out.
     
  4. David Grigor

    David Grigor TCMAS Old Timer
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    My gut feel is it's something else unless your dealing with sky high phosphates. I once tried adding some nitrates to try to get better algae growth on turf scrubber and reduce phosphates. It didn't really help that I could tell but I was also being very conservative with nitrate additive.

    I'd shy away from trying to get higher bacteria levels just in case it may be related and make thing worse. For me and rtn, the main two things to focus on are alk levels ( get them as close to 7dkh as possible ) , double check - triple check your salinity mesurements are correct. If salinity is actually higher than your readings ( 1.030 for example ) that will cause rtn.

    Before I'd resort to adding nitrate I'd make sure all nitrate reducers are removed such as deep sand beds, any bio media, rubble rock etc. Anything that could reduce nitrates and see what happens ( longer term ).
     
  5. marty9876

    marty9876 Banned
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    Verify test kit results to make sure the numbers really are true for starters. Jonty dosed no3 but he had active carbon dosing going (pellets).
     
  6. Jonty

    Jonty I contributed!
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    Drop your alk to 7.5-8
     
  7. abhishek

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    With no nitrates and alkalinity that high of 9.2 might be the cause of RTN. As @Jonty suggested, get it down below 8 and test from there .

    Regards,
    Abhishek
     
  8. OP
    Adam G

    Adam G Born to Reef!
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    Thanks for the replies guys. I will lower alk and keep working on phosphates and see what happens.
     
  9. dirtrider225

    dirtrider225 Junior Member
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    Make sure to drop it slowly, any change (even for the better) too quick is bad. Im sure you know this already, as do most reefers that have found their way to a forum buuuuuut it never hurts to reiterate lol
     

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