I've read it somewhere on here that STN from the base up could be due to lack of Iodine/iodate. I've searched to try to find the exact thread but have been unsuccessful. I'm sure it was mentioned by RHF, but can't find it now. Consider adding a bit of iodine/iodate. RHF doesn't like Lugol's.
I'll ask for myself and others. Do you run GFO? Is so, for how long and how fast do you reduce phosphate with it?
How many fish? I can find only one in your pics.
My ICP test did call out my Iodine for being low, and honestly I can't remember a time when it hasn't called out my iodine for being low. Testing for iodine is such a pain that I've been loathe to dose it (I don't like dosing when I can't test it easily... and while accurate, I'd hardly call ICP testing easy since the turnaround time is so long), but it's worth trying and I do have iodine on hand (not Lugol's).
I don't run GFO by itself, but I believe that Chemipure Blue has GFO in its mix. Since I added the Chemipure to my filter cup, my phosphate has gone down by 0.2 ppm over the course of about 4 weeks.
There are currently six fish in the tank:
- Melanurus wrasse
- Pink skunk clown
- Forktail blenny
- Japanese golden hawk
- Purple firefish
- Tomini tang
I’ve always kept my alk between 7-7.5dkh
And have read maintaining higher alk takes a highly skilled aquarist .
Lighting ... what lighting are you using ?
Seams to be very white , start with lower placement and slowly work the way up to where you want them .
to rule out parameter swings such as alk .
test every day at the same time and see how much everything fluctuates .
the goal is to aim for stable alk , cal and mag .
Ph will fluctuate between day and night as c02 isn’t consumed as much at night .
I would like to keep my alk between 7-9. I'm not dosing - it creeps up regardless of what I do. I test 4x a day (Apex Trident), and it'll slowly creep up between 0.1 - 0.2 dKh per day. I would like to have everything relatively stable - and technically, my numbers are stable right now. They're just higher than I want them to be.
My pictures appear significantly more 'white' than the real-world light does; I adjust the white balance to better show contrast, otherwise everything is just blue on blue on blue. I also sometimes use a filter over the lens to counteract the blue. I'm not exactly an expert, though, so it's a little tough to get the balance just right. Regardless, don't take the pictures as indicative of the lights. I use Ecotech's AB+ template on my Radeons, and my T5 bulbs are 2x Blue Plus, 1x Actinic and 1x Purple Plus.
Without correcting white balance:
After correcting white balance: