Raising nitrate/phos

[Willylumplump]

My tank is over 5 years old. I was able to keep sps for the first couple years, then all sps died out, lps died out somewhere over a year later. Tested often, did triton test, everything pointed to 0 nutrients, 0 phosphates, 0 nitrates.
Over the past few years, I have tried different things, reducing filter media, overfeeding, dosing nitrates and phosphates, all generally will raise nutrients, however gain unwanted algae. About every 6 months or so I would try another frag to see what happens, and always the same, It will last about a month. First week, looks great, week 2-3, color faded. week 4 tissue loss, slowly, everywhere, not top to bottom etc.

The tank will grow softies, and I had begun stocking with them, when I got the itch to try lps/sps again. So, I am removing more filter slowly, added more and large clean up crew to keep the algae down as I do it, and wondering suggestions on next step.
I removed bio pellets I was running, 1.5 cup on 250-275 system, small amount, phosphates bumped to .02 the week after, then have been back down to 0 for the past 2 weeks.
Suggestions on next move? I have 80# rock in sump. Should I start removing little by little? or should I start dosing nitrate and/or phosphate?
Tank is very mature, and sure someone will ask temp 78.5 salinity .025 ph 8.2 alk 8.2 phos 0 mag 1280 no3 0 k 390 ca 450

I was leaning toward removing rock, as it requires least amount of effort and $, but thought I'd ask for suggestions

 

[Marc2952]

The corals will die fast if there is no nutrients in your tank aswell as risking getting dinos which will just make things much worse. You need to dose enough phosphate and nitrates until your rock and sand is saturated and remains stable.

 

[Randy Holmes-Farley Verified Community Expert]

I think if you had unwanted algae, there was adequate nutrients for most corals.

If by unwanted algae you mean in bursts when dosing so you stopped dosing, then I suggest dealing with algae in other ways, such as herbivores.

I can't see removing rock being useful.

 

[Willylumplump]

I had same thoughts, if I had algae, then I had nutrients for the corals, but I can't find any other reason for inability to keep sps.
I found it quite odd, although I have some unwanted algae, and honestly it's not bad, I have 3 tangs and a rabbitfish, my macro algae doesn't really grow either until I raise my nitrates

I removed all sand over a year ago, I had a massive dsb in 58gal refugium, and removed from main tank as well

Guess I will start dosing

 

[Willylumplump]

Tank shot for point of reference, pics are about 6 months old, but not much changed

 

[dungdatinh]

Dose KNO3

 

[Willylumplump]

Mixed 2 cups kno3 with 1 gal ro. 10 ml day gives 2ppm nitrate fro my volume. I had a carpet algae type on my rocks, almost all gone by the new cuc. I have noticed macro algae in my fuge growing, and coralline algae caking up faster, no additional unwanted algae. Give it a few more weeks before adding a stick.

 

[Randy Holmes-Farley Verified Community Expert]

Sounds good.