Lost 3 frags and several colonies RTNing

[Caliguy1983]

I have had a very stable tank for several years. I basically ran a poor mans triton method. Last month my rockwork crashed and I started doing more water changes to combat the mess it made. I also went from fritz salt to basic instant ocean. My alk started jumping and got up to 11.4. I brought down to 8.9 or so over the period of a week. In those days some of my corals started RTNing. 3 of my torts did and I lost a WD and some reefraft frags plus a milli colony. I thought I brought it down slow enough but apparently not. Do you think the alk swings caused the RTN.

Alk- 11.4 dropped to 8.9 in a week
Ca- 465-475
Mag- 1500
Nitrate 5ppm
PO4- 0.03
Salinity 1.026

 

[ycnibrc]

I don't think so since I brought mine down from 8.9 to 7 in 3 days and I have no problems. Nutrients swing is more damage to corals.

 

[Mr. Brooks]

I recently had some minor STN from an alk swing. So it’s certainly possible. I’ll never raise alk more than 0.5 in a day from now on.

 

[DesertReefT4r]

Yeah the alk change could have cause it. I like to let high alk drop on its own. xould be a combo of issues though. Your crash combined with unstable and large alk swings both create instability in the tank potentially stressing and weakening corals. STN and RTN can be so hard to find a cause for.

 

[jda]

I had my alk swing down to 4.x twice in the last year when I ran out of Co2 and then had a line come undone and I did not notice. Everything is OK. I only run between 6.8 and 7.0, but still a bit of a jump. I just dumped in enough baking soda to get it back up in a few minutes.

IMO, alk swing can be the final straw for a coral, but will not cause a death on it own to an otherwise healthy and happy coral. I know that this is probably not a popular opinion of observation.

Can you let us know what lights you are using? I am starting to see and track some patterns where alk swings are more likely to do damage under certain types of lights and not so much others. Any data point would be nice, if you do not mind.

Keep on using the IO - it is a great salt. Add some Muratic Acid to lower the alk in your fresh mix. dKh drop * gallons * .123 is the number of mls of Muratic Acid to use. You need to let it aerate for a few days to drive off the excess co2 and let the pH come back up. I add a bit of dowflake to mine to raise the calcium.

 

[Caliguy1983]

I had my alk swing down to 4.x twice in the last year when I ran out of Co2 and then had a line come undone and I did not notice. Everything is OK. I only run between 6.8 and 7.0, but still a bit of a jump. I just dumped in enough baking soda to get it back up in a few minutes.

IMO, alk swing can be the final straw for a coral, but will not cause a death on it own to an otherwise healthy and happy coral. I know that this is probably not a popular opinion of observation.

Can you let us know what lights you are using? I am starting to see and track some patterns where alk swings are more likely to do damage under certain types of lights and not so much others. Any data point would be nice, if you do not mind.

Keep on using the IO - it is a great salt. Add some Muratic Acid to lower the alk in your fresh mix. dKh drop * gallons * .123 is the number of mls of Muratic Acid to use. You need to let it aerate for a few days to drive off the excess co2 and let the pH come back up. I add a bit of dowflake to mine to raise the calcium.

Using ATI 8 bulb T5 with one reefbrite XHO blue

 

[zack801]

I had my alk swing down to 4.x twice in the last year when I ran out of Co2 and then had a line come undone and I did not notice. Everything is OK. I only run between 6.8 and 7.0, but still a bit of a jump. I just dumped in enough baking soda to get it back up in a few minutes.

IMO, alk swing can be the final straw for a coral, but will not cause a death on it own to an otherwise healthy and happy coral. I know that this is probably not a popular opinion of observation.

Can you let us know what lights you are using? I am starting to see and track some patterns where alk swings are more likely to do damage under certain types of lights and not so much others. Any data point would be nice, if you do not mind.

Keep on using the IO - it is a great salt. Add some Muratic Acid to lower the alk in your fresh mix. dKh drop * gallons * .123 is the number of mls of Muratic Acid to use. You need to let it aerate for a few days to drive off the excess co2 and let the pH come back up. I add a bit of dowflake to mine to raise the calcium.

+1 on the muriatic acid to better match your current tank alk. I’ve done this with my growout tank water change water and I think thisbextra stability has made all the difference. Depending on your total volume if you’re normally around 8-9dkh and your doing a large enough water change with 11dkh then imo it could spike your alk enough to cause issues.

 

[Caliguy1983]

There’s 150 total gal and I only change 10% so it doesn’t make that much of a difference. The tank ca/alk consumption went way down and the dosers pumped the normal amount I was consuming all week is what got it up there. I’ve since been testing everyday to find the sweet spot and dropped the dose. Very frustrating to have a tank that was on cruise control for nearly two years and boom changes overnight.

 

[DesertReefT4r]

It happens and its always fast. Remember nothing good happens fast in a reef tank. I would never recommend changing alk quickly. If your alk is higher or lower than normal first thing you need to do just look at your reef, check your coral, check your fish, is everything looking good/normal.... If so thats good your reef adjusted to the change because it was slow. Now slowly make changes over a few days that way the reef can adjust to the change again. This goes for anything that many happen, check your reef see if everything is ok, dont panic and make several large changes. For example a few days ago my normally crystal clear water went cloudy and PH dropped for 8.15 to 7.98 at the same time, bacterial bloom. I checked the reef and my fish and inverts and all was well, did a water test and other than lower ph my tests can out normal, po4 had dropped some. It happened on water change day so I did my normal water change and just let it ride. 2 days later the tank was crystal clear again and I did nothing, no fixes no chemicals.

 

[Caliguy1983]

Still have a couple colonies STNing now. I’ve been trying to think of any major changes I’ve made. One is I started dosing vibrant once a week. The second is for two years I used fritz salt and recently went to instant ocean. I still maintain the alk swing was what did this but it’s mind blowing to me that a tank can run so well for a few years than go sideways in a week. I’ve been keeping reefs for almost 20 years.

 

[maroun.c]

Maybe, maybe not but the combination of alk rising then dropping fast and the change of the chemistry with the changes u made can very much cause that. I'd go slower with any change.

 

[Stickboy15]

One little thing and they go up in flames. If I have 1 start stn normally the one next to it will go up in flames that’s why if I have one go up I move it away and place it on the frag rack isolated on one of the tank but still in good flow and lightning