Tank crash unknown reason

Aki Madafaki · 2026-07-24T05:04:05-0400

So about 10 days ago i decided to test the theory that SPS need mature tank and i got some good deal on 6 sps corals, 3 acros one sthylo and one pocilo and one plateing monti. My tank is 3 months old and i had one cheap single speed wave maker, pair of clownfish, 4 snails, couple of moshrooms one frogspawn and one snall hammer frag. On the day i added sps i also changed my wave maker and i replaced it with 2 hygger minis. Moning after everything was closed up and stressed and i figured it to much flow for my 20g tank so i removed one. After 2 to 3 days my acros bleached and my clownfish were in sever shock, i places them in qt tank, one survived and one died, i alo removed all new corals only left stylo because it was the only thing in the tank that was doing good. Tank recovered and it was doing good for 4 days and yeaterday i again noticed all my corals closed up and my fish breathing rapidly. Temeprature was the same whole time, salinity was the same, kh was good at the time of the first charsh about 8.4 and now i noticed it dropped to 7.7. No stray voltage, did multiple 10% and one 35% water cnage in the meantime, added fresh activated carbon 10 days ago. Amonia is at 0. Only think is i dont know what is the PH and can that cause the chras. Check the video below and Please help

kevgib67 · 2026-07-24T06:58:37-0400

Sorry but no video is posted.

Aki Madafaki · 2026-07-24T07:44:16-0400

My bad here it is

Subsea · 2026-07-24T08:53:09-0400

Aki Madafaki said:
So about 10 days ago i decided to test the theory that SPS need mature tank and i got some good deal on 6 sps corals, 3 acros one sthylo and one pocilo and one plateing monti. My tank is 3 months old and i had one cheap single speed wave maker, pair of clownfish, 4 snails, couple of moshrooms one frogspawn and one snall hammer frag. On the day i added sps i also changed my wave maker and i replaced it with 2 hygger minis. Moning after everything was closed up and stressed and i figured it to much flow for my 20g tank so i removed one. After 2 to 3 days my acros bleached and my clownfish were in sever shock, i places them in qt tank, one survived and one died, i alo removed all new corals only left stylo because it was the only thing in the tank that was doing good. Tank recovered and it was doing good for 4 days and yeaterday i again noticed all my corals closed up and my fish breathing rapidly. Temeprature was the same whole time, salinity was the same, kh was good at the time of the first charsh about 8.4 and now i noticed it dropped to 7.7. No stray voltage, did multiple 10% and one 35% water cnage in the meantime, added fresh activated carbon 10 days ago. Amonia is at 0. Only think is i dont know what is the PH and can that cause the chras. Check the video below and Please help

“So about 10 days ago i decided to test the theory that SPS need mature tank and“

@Aki Madafaki
Not knowing your skill level, I hope you realize that your test was not very prudent. I also challenge your title “Crash for unknown reason”. I think the reasons are very obvious.

Also your videos are of little value for diagnostic troubleshooting.

Test that you should be doing are alkalinity, ammonia, nitrate & phosphate.

Aki Madafaki · 2026-07-24T09:01:53-0400

Subsea said:
“So about 10 days ago i decided to test the theory that SPS need mature tank and“

@Aki Madafaki
Not knowing your skill level, I hope you realize that your test was not very prudent. I also challenge your title “Crash for unknown reason”. I think the reasons are very obvious.

Also your videos are of little value for diagnostic troubleshooting.

Test that you should be doing are alkalinity, ammonia, nitrate & phosphate.

So can you explain the obvious reason to me please?

allof fish · 2026-07-24T09:01:58-0400

To me sounds like something more bacterial. I don’t believe just adding acros will cause everything to struggle even if the sps does. I would definitely test everything first and see if that gives an explanation. Did you dose or add anything else?