Big problem high alk,cal low mag

[Omrid]

I have 175g tank I'm going to do a 30 gallon water change and change my miracle mud,what should I do to even it out I lost 2 fish all my snails and star fish
Mag870
Alk14.7dkh
Cal 540
Nitrate 80
I know the nitrates high

[nlgill13]

do a water change (25%)....how often do you do WCs? Also what type of salt are you using? Do you have coral and what types (ie SPS, LPS, softies).

You might want to take a water sample into the LFS and have them test for comparison (usually costs a $1 or two per test).

[Omrid]

I have one hard coral bleached out 2 ananomes 1 leather 1 hard all looks like crab everything is dying out ph is 8.1 -8.2

[Omrid]

And I'm using instantocean when I finsh what I have I'm going to get redsea

[Im14abeer]

You can make mag supplement with Epsom salts. 8 oz by weight of the Epsom salts and enough ro/di water to make a pint. Add 4 oz at a time to a high flow area, preferably the sump. How did your alk and cal get so high in the first place? I would do two 30 gallon water changes a week while supplementing the mag until your levels come into normal ranges. Also, search up the Randy Holmes Farley articles on these parameters to help your understanding of the subject.

[Omrid]

We'll my tanks running like 7 years my brother set everything up it was his hoppy he passed away 5 years ago and my other brother was taking care of the tank till he stopped so no one took care of it for over 2 years my mom just feed them that's all so thank god only that happened

[Im14abeer]

Was the tank topped off with tap water for that two years? If so, that's probably how the parameters got so out of whack. Do you have an ro/di filter, because if it was tap water that skewed your numbers, and you make up saltwater with that water, things are just going to get more out of whack.