How to test for toxic chemicals in tank?

[kingkai512]

Hello,
its quite a long story but after leaving the tank fallow for 6 weeks i believe something is disturbing the water quality of my tank.
Either an overdose of Ruby reef rally pro or possibly a rogue rock that absorbed some chemicals (both of which were added before the fallow period). Oddly enough, the shrimp are still alive and well along with the hermit crabs.

After the 6 week fallow, i tested a fish to see how they would handle the water and they immediately acted as if there was no oxygen in the tank or ammonia poisoning. Swimming directly in the flow, signs of hypoxia, very rapid gill breathing swimming at the surface. I had to place them back in the QT tank and they recovered and started acting their normal self.

I did a 90% water change and readded the fish a few days later and they only lasted 3 days until the same symptoms happened again...once more i put them back in the QT and they were acting normally.

How can I test to see whats in my tank causing this? My parameters are below, it is a 220 gallon with a 30 gallon sump

ALK-10.9 DKH
PH 7.7
PHOSPHATE 0.2 PPM
CALCIUM 466 PPM
MAGNESIUM 1375 PPM
AMMONIA 0
NITRITE 0
NITRATE 20 PPM
SG 1.025

 

[LiLinka]

Just buy an ICP test for like $30

 

[taricha]

For this kind of a response something has to be badly off.
There is a bunch of stuff I can think of that could be off that might not show on ICP.
Rally Pro sounds like it could have some strong stuff in it that you'd rather not overdose. Short of a 100% water change, I don't have any good ideas.

 

[kingkai512]

Would a mass die off of hair algae and dinoflagellates produce a toxin? or a starfish death? I have been running carbon since the Rally pro dosage back in january and have changed it several times

The same shrimp and crabs are still alive through this whole ordeal

 

[Dan_P]

Hello,
its quite a long story but after leaving the tank fallow for 6 weeks i believe something is disturbing the water quality of my tank.
Either an overdose of Ruby reef rally pro or possibly a rogue rock that absorbed some chemicals (both of which were added before the fallow period). Oddly enough, the shrimp are still alive and well along with the hermit crabs.

After the 6 week fallow, i tested a fish to see how they would handle the water and they immediately acted as if there was no oxygen in the tank or ammonia poisoning. Swimming directly in the flow, signs of hypoxia, very rapid gill breathing swimming at the surface. I had to place them back in the QT tank and they recovered and started acting their normal self.

I did a 90% water change and readded the fish a few days later and they only lasted 3 days until the same symptoms happened again...once more i put them back in the QT and they were acting normally.

How can I test to see whats in my tank causing this? My parameters are below, it is a 220 gallon with a 30 gallon sump

ALK-10.9 DKH
PH 7.7
PHOSPHATE 0.2 PPM
CALCIUM 466 PPM
MAGNESIUM 1375 PPM
AMMONIA 0
NITRITE 0
NITRATE 20 PPM
SG 1.025

Are you using GAC?

 

[Kathy Floyd]

Following

 

[kingkai512]

Are you using GAC?

PREMIUM activated carbon from marineland haha, a step beyond....maybe