Tank issue stressing shrooms

[mushy coral]

my tank is a 45liters shallow frag tank, currently 7months old and keep only softies, mostly mushroom. The tank been through cyano once and been stable for 3 months till now cyano came back and this time somehow all my shroom got their mouth wide open which i didnt see in the first cyano bloom. Got 2 rhodactis died few days ago because of low mg and kh, heres the water param now:
Kh 7.7
Ca 400
Mg 1310
No3 15
Po4 0.25
Fixed the low kh mg issue, is cyano the reason that stressing my mushrooms? If it is then its strange that when the first cyano bloom my shrooms did not stress like this. Any idea of anything affecting my shrooms? Thanks in advance!

 

[Matt Bravo]

How quick did you increase your parms? If it was in a short time span then it’s likely they’re feeling stressed due to the instant change

 

[mushy coral]

How quick did you increase your parms? If it was in a short time span then it’s likely they’re feeling stressed due to the instant change

Kh 6.7-7
Ca 400
Mg 1270
No3 20
Po4 0.3

I got from this to the current parameter after 3 wc in a week. But i noticed the strees before i do the wc so i guess is not because i raised the param too fast.