Hi - I’m looking for some ideas on what might going on with my PO4 numbers. I do have a theory but I’d like to see what comes out of the discussion.
At night it appears my PO4 varies between .101 and .03. During the day I’m seeing numbers between .08 and .15
When my PO4 is spiking I can see the difference in the corals which is leading me to do additional testing (Polyp retraction, change in colouration)
Testing wise - I use the Master Tronic with the Tropic Marin Pro PO4 testing kit, and the Hanna PO4 ULR tester. Originally I had some inconsistencies in the readings until I fixed the PO4 Master Tronic vial (sulphuric acid had eaten through the lid and polluted the reagent) - and now they are fairly consistent with each other so I’ve ruled out the test kits being the issue.
I do carbon dose Elimini NP which does over time lower PO4 nicely however I stopped carbon dosing for a couple of months during my dinoflagellates battle. Similarly I also stopped
my skimmer during this period. Regardless for the last 8 months or so (which is a time period outside of the dinoflagellates battle) the PO4 has been consistently up and down in an unpredictable manner.
I do use live rock from 2 different sources - both sources got them from the ocean a few years ago and since then they havein tanks (Indonesian).
I have live rock both in the sump and in the tank - probably more lbs/gallon than I need. The sand bed is very much alive and healthy. I have a goby that cleans it nicely.
The only thing I can see as being a possible cause is I use an alternating light schedule for the refugium. The refugium has no Chaeto in it - but live rocks, snails and copepods. There is a small amount of algae as well but nothing major.
I feed once a day - 3 cubes for a tang, wrasse, 2xclowns and a goby. It’s a little heavy but my bio load is pretty light
I really don’t know what’s causing such a big variance but it is impacting the health of the corals.
Thanks In advance for your suggestions and insights
At night it appears my PO4 varies between .101 and .03. During the day I’m seeing numbers between .08 and .15
When my PO4 is spiking I can see the difference in the corals which is leading me to do additional testing (Polyp retraction, change in colouration)
Testing wise - I use the Master Tronic with the Tropic Marin Pro PO4 testing kit, and the Hanna PO4 ULR tester. Originally I had some inconsistencies in the readings until I fixed the PO4 Master Tronic vial (sulphuric acid had eaten through the lid and polluted the reagent) - and now they are fairly consistent with each other so I’ve ruled out the test kits being the issue.
I do carbon dose Elimini NP which does over time lower PO4 nicely however I stopped carbon dosing for a couple of months during my dinoflagellates battle. Similarly I also stopped
my skimmer during this period. Regardless for the last 8 months or so (which is a time period outside of the dinoflagellates battle) the PO4 has been consistently up and down in an unpredictable manner.
I do use live rock from 2 different sources - both sources got them from the ocean a few years ago and since then they havein tanks (Indonesian).
I have live rock both in the sump and in the tank - probably more lbs/gallon than I need. The sand bed is very much alive and healthy. I have a goby that cleans it nicely.
The only thing I can see as being a possible cause is I use an alternating light schedule for the refugium. The refugium has no Chaeto in it - but live rocks, snails and copepods. There is a small amount of algae as well but nothing major.
I feed once a day - 3 cubes for a tang, wrasse, 2xclowns and a goby. It’s a little heavy but my bio load is pretty light
I really don’t know what’s causing such a big variance but it is impacting the health of the corals.
Thanks In advance for your suggestions and insights