My phosphates were consistently high!

Rubber Ducky

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Apr 6, 2021
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After months of super high phosphates, I realized I've been to blame this whole time! Well, a little 70 gal has been up for 1 year and 3 months, and for about 5 months, I have been having super high phosphates, like .18 ppm displayed on my hannah ulr tester!! I use 4 stage ro/di for my water, Ive run GFO, and I would change out 21gallons ro/di water mixed with red sea pro about once a week, and did 50% water changes every 3 weeks and my phosphates would still be 0.12-0.18, like everytime (tested 2 times per week 24-48 hours after water change, then again before I changed out in a nut shell, nothing changed...water looks beautiful, some corals look stressed, others are doing great, and lost a cpl high ends, bummer....anyways...I finally tested my phosphates from a fresh batch of ro/di and go figure, 0.18!!! So low and behold I switched out my filters, which I now know we're overdue for a changing...bam, 0.05ppm!!! Sooooo, guess who is gonna go do a 50% today and make my tank super happy!?!?!

Lesson learned, my tap water sucks for ro/di, and I have to change out my filters about every 4-5 months! If anyone is having problems like I had, go back to source and test from there and hope this lesson I learned can help others...happy reefing all!!
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