Phosphate and nitrate

GMan1974

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Hello everyone. I have a 20g JBJ RIMLESS nano tank with 2 clowns, 1 banghai, 1 firefish, 1 RGB. Hermit crabs 1 pistol shrimp. 1 skunk cleaner shrimp. Snails, 1 pin cushion urchin. I did a 50% water change last Saturday. Brought my phosphate down to .17 ppm from .30. My nitrate went from 26 ppm to 14 ppm.
5 days later my phosphates are .30 ppm and nitrates are 24 ppm. I give a a single pinch of food per day. I run a protein skimmer. I still have diatoms.
What am I doing wrong? Thanks.
Glenn
 

Randy Holmes-Farley

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The phosphate rising after the water change is the expected result of having most phosphate bound to rock and sand. Even a 100% change may only make a small dent in the phosphate once it re-equilibrated. That is why water changes are not a great way to reduce phosphate.

That said, your levels are also fine and I would not overly worry about them.

There are many good ways to deal with rising nutrients, such as growing macroalgae, an ats, organic carbon dosing, GFO, etc.
 
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GMan1974

GMan1974

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I have also been using seachem phosguard to help lower the phosphates.
 

Randy Holmes-Farley

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Wants corals eventually.

The values right now are fine for corals. I recommend 5-50 ppm nitrate and 0.06 to 0.3 ppm phosphate, but higher levels are also ok.

You values now match mine at 0.34 ppm phosphate and 14 ppm nitrate at my last test.

IMG_5580.jpeg
 
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GMan1974

GMan1974

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The values right now are fine for corals. I recommend 5-50 ppm nitrate and 0.06 to 0.3 ppm phosphate, but higher levels are also ok.

You values now match mine at 0.34 ppm phosphate and 14 ppm nitrate at my last test.

IMG_5580.jpeg
 

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GMan1974

GMan1974

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Great looking tank sir. Thank you for the advice. I appreciate it.
Glenn
 

jeffmr4

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That's a big pincushion urchin! My nitrate is 0 I think and I haven't tested phosphate in a while but everything looks good in the tank. I have some gracalaria hayi macroalgae which outcompetes other algaes pretty well. I also have a small skimmer and an hob with carbon/floss cartridges. Tank looks nice!
 
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GMan1974

GMan1974

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That's a big pincushion urchin! My nitrate is 0 I think and I haven't tested phosphate in a while but everything looks good in the tank. I have some gracalaria hayi macroalgae which outcompetes other algaes pretty well. I also have a small skimmer and an hob with carbon/floss cartridges. Tank looks nice!
Yes when I ordered him I forgot to ask size. He's big!! Like a tennis ball.😂
Thank you!
 

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