ph was at 9 when woke up

system is 6 months old and has been stable.
System was running at
3.2 kh
410 cal
1380 mag
8.2 ph

stock list in dt:
1 coral beauty
1 six line
1 pulsing xenia
snails and 2 brittle stars


my tank was very cloudy this morning and ph was at 9 testing with tropic marin kit, my rkl proke went bad 2 days ago of coarse. I performed a 20g wc on 115g total volume system and added 1tbl spoon vinager to get ph headed in correct direction again.

8:30am
ph 9
alk 3.2

9:00am after wc ph is 8.6

10:30am
kits are salifert except the ph is tropic marin

Ph 8.4 dropping on its own now
mag 1380
cal 440
alk 2.5 (dropped)
phos 0
amm 0
trites 0
trates 0

Now seems ph is dropping on its own which is good however I need to get alk back up.
I have been using 4 tsp baking soda every morning to keep kh at 3.2 and 6tsp cal every night to keep cal at 410 although cal dosing has been giving me problems trying to get correct dosing amount, I also run a lime ato on float switches. should I use baking soda slowly to get alk back up which will help bring ph back down or switch to a buffer for the alk? not sure why the crash unless I didnt need soda dosing over the last 2 mornings and dosed it anyway. I test every 2 days or so for kh, I missed one morning of soda dosing and kh fell to 2.8 24 hrs later when I tested to see where it was.
Since last night I do have this white fleshy spider web looking stuff swaying and extending from one rock and is attached to some areas on the glass and overflow box. I have a brittle star thats mia so maybe this is him however no amm, trites, or trates. my tank was very cloudy this morning also but is clearing up now very nicely. since the ph is dropping on its own should I just wait to see where it goes before I try to adjust the kh? what is the white spider web looking stuff? should I remove the rock to clean it and scrub the glass or not?
Thanks for any advise

 

How fast is your ATO pump? Lime-water often can cause a precipitation event if added too fast and not diluted fast enough. Some people luck out and have no "apparent" issues, while adding it at a relatively faster rate. However, IMO and IME, it really should never be added faster than a moderate drip.


Anyways, Randy discusses what to do in the case of a lime overdose here.
What Your Grandmother Never Told You About Lime by Randy Holmes-Farley - Reefkeeping.com

 

aqua lifter, its not presipping

 

adding vinegar is carbon dosing and could create a bacterial bloom. not sure of your tank size but you really need to be careful with vinegar . kalk alone should keep your ph stable. i dose kalk threw my ato to keep my ph stable.

 

Dt is 75g total volume is 115g, I agree and I only added 1 tbls vinager to help get the ph going back down after a 20g wc, i also dont like chemicles as it seems to start a chain reaction of trouble to correct. Like you I only dose lime to keep ph stable through my aqua lifter ato and my system requires 4 tsp of baking soda every morning at 6am to maintain my 3.2 meq level.
My ph stablized at 8.2 on its own as of 3pm so I added 4 tsp soda to help bring alk back up and restarted my lime top off to help maintain the 8.2 ph. The white spider web looking thing has disappeared as fast as it appeared, not sure what the heck happend. I think i'm back stable again and the xenia is working its way back out. I know my skimmer is skimming like crazy but that could be the missing brittle star i suppose.
My setup almost runs itself, very stable, maybe the salt lords wanted to wake me up or just needed a good laugh for the day, who knows
Thanks for all the help