Recently I came into an issue getting water for my tank that led to not having a water change done in over a month. For the first two or three weeks things seemed fine, I was still making sure to dose calcium magnesium etc. and the corals for better or worse seemed alright. Last week, a few of my euphilia started showing major signs of tissue recession. I went ahead and made the arrangements to be able to mix my own salt at home and went to town changing water yesterday. Because of how high the nitrates were (50+ppm ) I decided to do two large water changes 4-6 hours apart. (40-50% each) This brought my nitrates down considerably back into what I would consider acceptable levels for my system (10-20 ppm). Fast forward to the next day, 2 of my 3 torches/hammers are showing significant improvement. I'm talking double of the polyp extension and plumpness. Well the torch that I've had the longest (and is in the process of splitting its one head into three) isn't doing any worse but it's not nearly as much of an improvement as the other two.
This finally leads into my question, is it dangerous / harmful to do such large water changes so close together and change the nitrate level that rapidly? I use red sea coral pro salt mixd to 1.025 and use Red sea foundation skeletal elements ABC+ to maintain parameters between water changes. After the salt mixed everything calcium alkalinity magnesium wise matched the levels before the water changes. So I didn't drop or raise any of those significantly just the nitrates.
This finally leads into my question, is it dangerous / harmful to do such large water changes so close together and change the nitrate level that rapidly? I use red sea coral pro salt mixd to 1.025 and use Red sea foundation skeletal elements ABC+ to maintain parameters between water changes. After the salt mixed everything calcium alkalinity magnesium wise matched the levels before the water changes. So I didn't drop or raise any of those significantly just the nitrates.