No announcement yet.

Prime Overdose?

  • Filter
  • Time
  • Show
Clear All
new posts

  • Prime Overdose?

    Hi There,

    I want to see if Prime can be overdosed and if this will cause any problems on later stage when livestock introduced?

    I had to disinfect a marine fish system with a chlorine. After water changes and washing used water off, chlorine concentration still was over 3mg/L total system volume is 3000L. I added 500ml of prime and it seems it did a job. Chlorine is not detectable now.

    Question is did I added too much? Is it safe?

    Thanks in advance.

  • #2
    Re: Prime Overdose?

    While I have no idea of the effects of a serious overdose of Prime, I can give you the required dose for your tank volume. Your tank volume only requires about 79.2 ml to neutralize chlorine. According to the page for Prime, this dose will neutralize 5 mg/l of chlorine (am I correct in this?). If it were nitrites and the dosage was 5x, it would only be about 396 ml. I would leave the overdosage effects to the experts.


    • #3
      Re: Prime Overdose?

      Thanks for your question, Aquaworld. As far as direct toxicity, overdosing Prime isn't any concern. It won't poison your fish. It is a reducing agent, so what can cause an issue when over-dosed is that if there aren't enough other things in the water to react with, like nitrogenous waste or chlorine, it will react with and reduce oxygen. This can suffocate the inhabitants of your tank.

      It sounds like you used it in an aquarium which doesn't have livestock yet, in which case it poses no danger. Prime only stays active in a system for about 48 hours.

      Detailed directions for dosing Prime can be found here: