25% weekly water changes with acropora?

[jeep and goose]

so im trying to figure out what would be ideal in terms of nutrient export for my 20 gal reef. its kinda heavily stocked and i was leaning to 25% weekly water changes to manage that. right now i have a small diamond goby (will be moved in a few months. might just rehome him though) royal gramma, citron goby, fusi goby, and 2 firefish, along iwth a coral shrimp and some various snails. my nutrients are kinda high right now, 0.389 phosphate (not 100 if thats accurate tho) and 22.5 nitrate. i was also considering skimming. problem is i have some green slimer i think and a blueish one with neon green polyps, also a pinkish brown looking one. i dont know names specifically. i know acro are sensitive to swings so maybe i do 10% biweekly, or also i could do 10% weekly i would have to get a hang on back skimmer if anyone has reccomendatiosn for that. i have a lot of soft coral and some macroalgae to help with nutrients too. and was considering gfo although im not sure cause i have some traces of dinos. they have been quite well behaved though. my alk was 9.9 last time i checked however i will check again in a minute. and idk my calcium i will check though. also, i plan to dose all for reef to keep my traces up. would it just be advisable to keep it around high 9? i am not trying to run low nutrients but i dont want my nutrients to be outta chekc

 

[jeep and goose]

i just read that reef crystals has about 12 dkh, should i try to slowly rise mine

 

[Science/G]

I wouldn't go up to 12. Alkalinity in natural seawater is around 8. 9 is fine. A skimmer will help control your nitrates over time, and will help with gas exchange, so that's not a bad idea. A little bit of gfo in a bag will bring those phosphates down , but do that slowly. 10% water changes are the way to go. And if you're doing regular water changes and dosing all for Reef make sure you monitor your alkalinity. Until those corals start to grow and start consuming you might see an unwanted Spike in alkalinity