High nitrate and phosphate?

[MACHO]

Hey everyone so just in the last hour I tested nitrates and phosphate no3-42 and po4 .62 what in the world!! I did a 70 gallon water change on a 200 gallon system. Inhabitants sailfin tang blue powder,yellow,whitetail,2 clowns,2 cardinals, 1 anthias, 1 goby and 1 royal gramma. No idea I feed once a day rods frozen food which I wash with Rodi water 7 stage filter. Also I feed 1 sheet of nori about 4 out of the 7 day week. my Tds in is 20 and out is 0 went to the fish store this week and did a sample on my mixing water which is good grade 75 gallon barrels in the garage.

lfs guy told me that nitrate was probably wrong on my mixing barrel since the test spin isn’t exact. What in the world is going on? I have a bio pellet reactor filter roller skimmer and a refugium. Any help will be greatly appreciated.I have been testing with a Hanna checker as well as the lfs.

 

[PocketGoose]

How long has the tank been established?

 

[MACHO]

How long has the tank been established?

Since march of 2022

 

[PocketGoose]

Okay cool, started with dry rock? LR? I know rock can sometimes leech PO4 back into the aquarium.
Seems like the microbial community in your tank is not equip to handle your current bio load. Did you recently add more fish to the tank?

Some things you can do in the interim include water changes like you've done and adding some denitrifying bacteria might be helpful as well (MB7, or something similar). It seems like your frozen food addition wouldn't be the culprit, maybe the nori is pumped full of nitrates/phosphates and anything not eaten by the fish is leeching back into your tank.

Just curious, have you tested since you preformed the large WC?

 

[MACHO]

Okay cool, started with dry rock? LR? I know rock can sometimes leech PO4 back into the aquarium.
Seems like the microbial community in your tank is not equip to handle your current bio load. Did you recently add more fish to the tank?

Some things you can do in the interim include water changes like you've done and adding some denitrifying bacteria might be helpful as well (MB7, or something similar). It seems like your frozen food addition wouldn't be the culprit, maybe the nori is pumped full of nitrates/phosphates and anything not eaten by the fish is leeching back into your tank.

Just curious, have you tested since you preformed the large WC?

Yes as I tested yesterday night. I started with dr and live sand. Have not added any new fish in a while since most have either not been able to handle the community of the powder blue and very healthy anthias.

 

[chipmunkofdoom2]

Water changes don't do much for PO4. Phosphate binds to aragonite surfaces (rocks/sand). When you change water, the overall PO4 level in the water drops, but the rocks release PO4 until the water and the rocks reach equilibrium again.

People who have chronically low PO4 see this cycle, but in reverse. They dose PO4, then a few hours later, it's all gone. It hasn't been used, it's been adsorbed by the rock surface. If your PO4 is zero and you have very clean rock, you often find you have to add crazy amounts before you are able to measure any in the water column.

The best course of action would be a phosphate binder like GFO.

 

[MACHO]

Water changes don't do much for PO4. Phosphate binds to aragonite surfaces (rocks/sand). When you change water, the overall PO4 level in the water drops, but the rocks release PO4 until the water and the rocks reach equilibrium again.

People who have chronically low PO4 see this cycle, but in reverse. They dose PO4, then a few hours later, it's all gone. It hasn't been used, it's been adsorbed by the rock surface. If your PO4 is zero and you have very clean rock, you often find you have to add crazy amounts before you are able to measure any in the water column.

The best course of action would be a phosphate binder like GFO.

Currently I have a bio pellet reactor running