Acceptable levels of Phosphate and Nitrate while treating Dinos.

[Arsenix2001]

I have been in a war with dinoflagellates in my 75 gallon for 3 months and I'm finally winning. Been dosing bright wells neo-nitro, phosphate and microbacter 7 as well as sponge excel silicate. Everything is doing fine except for my green bird's nest has developed brown algae on the tips and polyp loss is starting from the tips back. This is been a happy large softball size colony I've grown from a frag over 2 years. All other types of birds nest and Monty seem okay. Zoanthids and mushrooms are thriving. I had my PO4 spike as high as .14PPM. Nitrate at 5PPM. I had an alk spike up to 12 DKH a few weeks ago but have been slowly bringing it back down to 9.3 currently. Targeting 8.6. I added phosguard to the tank yesterday and have brought my PO4 back down to .07PPM in an attempt to save the green bird's nest.

I don't want to however lose the progress I made with the dinos. I haven't had to vacuum the sand and almost 2 weeks. Just now starting to get slight coloration. At the worst it was coming back as a carpet every 2 days. I have not done a water change or run my skimmer in 3 months. Just changed my activated carbon yesterday. What is a safe level of PO4 and nitrate to run to still keep the dinos at bay but let the birds nest breathe a little easier and potentially save it? Trying to decide when to pull the phosguard.

 

[Spare time]

I find that just dosing it to the typical range is fine (0.03ish to 0.1 ish).