Fox coral bleaching, ideas

[rykone]

Ok so I have a fox coral bleaching. Pretty sure it is due to a series of changes over last weekend. I’m trying to figure best way forward. First tank info...
Tank is roughly 4-5 months old. It is my sons. He had a 20 gallon fish only for about 6 years. Decided to upgrade him to a 29 gal. We took all existing live rock and sand from old tank and transferred it to new tank. Reused all but four gallons of old water and old filter. Total switch less than an hour. Live rock and fish moved into 5 gallon buckets and sand dipped in and rinsed in 4 gallons of the old aquarium water before being placed in new aquarium. Nothing dried out. Did experience very slight ammonia spike about 2 weeks after switch. Was expecting this due to disturbing/rinsing the sand bed.
Ok. So fox coral was bought about five weeks ago. Took him a day to open up but since then was doing great until this week. This past weekend I decided to buy my son more coral. So Friday evening I did my weekly water change. I’ve been doing 3-4 gal water changes roughly every week. I checked salinity first and it was a little high by Hannah meter. Around 35.3. So I added some rodi water and brought it back down. Ended up reading 34.8. This I think is part of issue. I didn’t mean to drop it that fast. Less than an hour. I also didn’t realize my meter was off. So my salinity is now at 34. I also checked my parameters and my ph was low. Like 7.4. Which has been normal and I believed was flow related. Alk was also low before the water change at 7.8. Also somewhat common for this tank. I’ve been researching ways to fix this and am trying to decide on a solution. Ca was 450 and mag was 1460.
So next day went to Lfs. They didn’t have the pulsing Xenia but had a zoa frag he liked so bought it. The guy at the fish store convinced me I was running my lighting too dim for my fox coral. I also bought a hydor 240 power head to increase surface agitation and hopefully bring pH up. Got home. Installed power head and turned led blue from I think 65 to 100 percent. Acclimated zoa and went to sleep. Next morning noticed fox coral wasn’t open as far as usual. Zoa had fully opened. Had one astreae snail that was upside down. He fell off once more and I set him on some live rock. He crawled next to my fox and later died. I removed him. I tested parameters. PH was up to a little over 8 (I’m still using an api test kit. Not most accurate) Alk was 9.64 by Red Sea test kit. This was 12th. All other paeans tested good. Fox looking a little worse. Noticed he was wavier than usual since powerhead install and figured he was in return path. So moved powerhead. He’s kept getting worse. So yesterday I decided to recheck everything. Salinity meter was off. After recalibration my salinity is showing at 34 ppt. My ph was showing right at around 8. My Alk is 9.7. My ca was 460. And my magnesium is 1540. Call and mag have always been really steady in this tank but until I installed the powerhead my Alk and ph were stubbornly low. My ammonia was zero nitrites zero and nitrates around 5 ppm. When I say zero I mean undetectable by api test kit.
ok so I think I covered everything. I’m pretty sure that between the salinity swing, pH increase, Alk increase and lighting increase I’ve shocked this poor coral. I have lowered the led lights back down because he was doing good at the first level and I feel stupid now for just blindly raising them based on the lfs guy (which no offense he does know a lot about corals which is part of why I just followed his advice). I started last night trying to slowly raise the salinity back to 35. I’m up to 34.2 now....the Alk and pH I’m not sure what to do with...I feel it’s better to keep them high? Or rather at more normal levels than the low my tank normally has? I was checking and the coral has started to bleach around the edges.
I also have a clownfish, zebra dart fish, purple fire fish, five nassarius snails, seven astrea snails and a brittle starfish that came as a hitchhiker on the fox coral. All these seem to be doing good. The zoa has done fine this week although when I checked here about an hour ago he was closed up.
right now my plan is to try and slowly bring salinity up. I reduced lighting but should I reduce period as well temporarily? Is there anything else I can do other than keep an eye on parameters and go slow on return to normal? Before and after pics included. Hard to see bleaching in the last photo though. Any thoughts appreciated. I’m new to trying to grow corals. Thanks again

 

[Bo.]

First things first. Welcome! Lots of knowledge around here to lean on.

Secondly, slow down on the changes. Rapidly trying to fix a problem will make it worse than methodically figuring out the issue. A good rule of thumb is one change every couple of weeks so you can observe the impact of that one change.

The salinity isn't a huge swing at all. 34 to 35 won't affect your corals. A 240 in a 29g shouldn't be too bad unless it was blasting your coral directly for a couple of inches away. The ph was a little low, and the aeration seems to have done the trick, did you dose anything or just use the power head?, And what light fixture are you running?

Don't trust the api kit at all, get a basic nitrate/ammonia/phosphate to start with from a reputable company like Salifert/red sea/Hanna and then you can make changes slowly based on accurate testing. At this stage your water changes should have you covered on calcium/magnesium. You don't really have enough corals to deplete what is in most commercial reef salts.

That is a lot of changes in 5 days! Regardless of the original issue,

Just remember this hobby is a marathon, not a sprint. Small changes one at a time. You corals will reward stability and perseverance.

 

[rykone]

Ok deep breath, and relax. First thanks for the reply! Second, before I forget let me answer the questions:
No I’m not dosing anything. I was on the fence due to the low Alk/pH. But I had researched and figured it was due to either low surface flow/agitation or possibly high co in the house. And even though I was at the lower end of recommended Alk I figured if I could get pH up I didn’t want to risk screwing something up with a mistake in dosing.
Lighting- I don’t know the brand. It’s a cheap light I bought before getting corals. Has no markings on it. I know I paid less than 100 for it. It is led and has two sets, an actinic blue and a white spectrum. The lfs guy said he wouldn’t recommend any leds except for two brands both of which were above three hundred. He said I likely wasn’t pushing enough light with the cheap one I had which is why I turned the blues up from 60% to 100%.
These were originally the only two changes I meant to make. The salinity change occurred during my normal routine of water changes. I don’t have auto too off so I usually either adjust with ro water or mix my salinity up a little under to compensate. Normally I’m less than .3 out and usually less than .2 out. I’ve never had an issue doing it this way. After calming a little I now don’t think it actually “swung” by 1 ppt during that change. I believe i changed it by maybe up to .5 ppt when I added rodi water. I believe the other difference was my meter and that it had been there for a while. Ie it was really only say 34.8 when my meter said 35.3 for example.
Having said all of that. I realize now I should have installed the hydor first and waited before adjusting the lighting. I also didn’t think of returning the lighting to the first value and moving the hydor as changes. But I can understand it now that I think. Especially since the purpose of moving the hydor was to change the flow.
As for the pH I’d decided to try the flow because it didn’t seem to change even with the windows open here and there. I retested today and Alk was at 9.8 and pH was showing around 8. Alk tested at 9.7 on Thursday and so I’m calling it steady. 0.1 diff is most likely error on my part. pH has been around 8 (api test kit) ever since the hydor was installed. It was reading 7.4 on api test kit until hydor was installed. So yes I believe the increased flow has fixed that issue. I’m going to leave everything alone for now. I moved my weekly water change up to yesterday and after changing two gallons my salinity is at 34.5. But between your assurance that that swing really wasn’t that big and the fact that I’m thinking it was prob running around that to start (meter off). I’m not going to worry about it too much. I’m also going to purchase better kits. I have a Red Sea kit for Alk cal and mag. I was trying to run out the api kit but I’m not sure I trust it anymore. I’ve been re-reading some articles by randy Holmes on how high nitrates can affect Alk and it’s making me wonder if my nitrates aren’t higher than what I’m detecting with my api kit. But for now I’m just going to keep testing to make sure my Alk and pH don’t nosedive, and let the tank settle. Side thought- could an Alk swing of 7.8 dkh to 9.7 dkh have caused an issue with this coral? And I know the flow helps pH but is it also why my Alk is staying higher? It usually would come up after a water change but then drop pretty quickly after- along with pH. I’m thinking based on what I’ve read if the flow lowered the co2 then that should help Alk as well as pH but I’m new to this. And thinking again though the Alk swing has been present at most water changes and not caused an issue with this coral (although it’s a new coral too so not a lot of water changes). Anyways I realize now I’ve started rambling. Bottom line is...all parameters look good so no chemistry changes planned. Leaving lights and hydor alone. No more moving around or changing intensities. Giving it time. Buying better test kits. Thanks again for your reply and time. I really hope he pulls out of it. Haven’t seen him out at all today and he’s looking a little whiter. The white is mostly at the edges. The zoas have been out but seem to be “alternating”. By this I mean one polyp will be open and another closed. Then a few minutes later they’ll be reversed. Not sure if that’s normal or not. But they’ve only been in tank for 6 days. Thanks again!

 

[rykone]

Update.
Fox coral extended very slightly today. Hopefully means he’ll start coming out over next few days. I’m leaning towards the lighting change being mostly at fault. Borrowed a par meter for like greenhouses (so no underwater values). Shows my light value at top of the tank at current levels around 170-185. When I turn it up to where I had it that Saturday it reads around 215.