Phosphate/Nitrate issue! Help please!

Reefingmama · Jul 20, 2020

Question: I’m worried my nitrates/phosphate is out of control... here’s my specs:

120 gal DT
30 gal sump
LPS looks ok. Sps is browning and slowly loosing skin (wrong word, I can’t think at 2am while rocking a Screaming newborn)
We did a 25% gallon change today to bring down nitrates and phosphates from 10 and .4 respectively. No visible algae, except a small amount on the glass. Tank was just moved 1.5 weeks ago and is 9 years old. Fish were added and some GSP covered rock was removed and switched out for dry reef saver rock. About 50-60% of the old rock was removed due to pests and unwanted corals. Fish are happy, healthy and eating. LPS looks colored up but SPS is brown.

Salinity 1.025
Nitrate 5 Salifert
PH 8.4 salifert
Calcium 420 api
Alk 9 Salifert (8.1 Red Sea)
Magnesium 1310 Salifert
Phosphate .13 Hanna

We are stocked fairly heavy with 4 tangs, 2 gobies, 1 wrasse, 2 clowns, 2 blennies and some shrimp

WIReefer · Jul 20, 2020

What do you all have in the sump?

Reefingmama · Jul 20, 2020

WIReefer said:
What do you all have in the sump?

Protein skimmer, BRS 2 chamber reactor running GFO and carbon

esther · Jul 20, 2020

Looks like your NO3 & PO4 are just fine. No need to panic.

laverda · Jul 20, 2020

I would not worry about your nitrates and phosphates at those levels. I suspect the issue is all the new rock. Lots of people have trouble when using dry rock. You got ride of some pests, but you also removed a lot of biodiversity. Dose some beneficial bacteria.

Aussiemarine · Jul 20, 2020

Yeah the spike would be because you removed the old rock and added new tock. If you removed 60% of the rock then you’ve lost a very large chuck of your beneficial bacteria. You’ll go through a mini cycle where your nitrates and phosphates are elevated whilst your ecosystem establishes itself again and balances out.