Hey Bella, thank you

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Recently I been tempted to put some more fishes in the tank but I had to hold off. I need some bottom dweller and my engineer goby is mia atm. Everyone is doing well.
Vinegar is use as CARBON source. But it’s not the same as Activate Carbon.
Vinegar, vodka, sugar, bio-fuel, bio-pellets etc. are used to able N/P loving bacteria to pollute which will eat but also produce good sources for the corals. Excess should be skimmed out and must go slow when starting whether you go with products like vinegar which are weaker compare to vodka and bio/pellet.
So it’s the way to use your N/P and also and feed your corals. I think…….
If you are having hard time holding your pH up, you should oxygenate your water.
So, good water changes with section of sand cleaning, good skimmer and aerate the water, turn off the heater and cool down the water for more oxygen, putting tons of flow in the tank as well as sump if you have one, co2 scrubbers to take out co2. ETC. Also using solution like Kalk helps with the growth and the pH.

. Vinegar in the Kalk solution allows me to dissolve more than it usually do by it also. Making it more acidic. And it is dosed with the Kalk solution for continuation instead all at once. Which is bad idea.
If you have alots of people and pets in the house or have bad flow of air, ph will be low. So put clean air “INTO” the tank.