Problems with corals

[Amy Dawson]

Hi everyone, my corals aren't doing too hot. Just wondering if anyone could give me some advice. This is what I'm losing mostly, I can't keep acans at all, they slowly start receding until the skeleton starts showing and then they're toast. Montipora also starts receding to show the skeleton. Open brain corals, lobo, total lost cause. Birdsnest corals I used to do pretty well with but now they're starting to bleach from the bottom up. My pectina coral has horizontal black lines on it. All the fish are doing great and so are Zoas for the most part. Gonipora does great as well. I have a mini max anemone that did great for a month and now is lying in the sand. Idk I love this hobby but it's so frustrating

It's a 50 gallon tank. Reef octopus skimmer, canister filter fluval, I use actual ocean water in the jug, change water every week (which is getting expensive), I have one wave machine, mars aqua LED lighting. My temp dropped last week to 73 from 78 because my heater broke. It was replaced immediately and temp went right back up. All of my basic readings are right on. The only thing that is a little high is the magnesium.

 

[Amy Dawson]

Here are some pics

 

[twilliard]

Starting to think this is stemming from the heater issue

 

[Amy Dawson]

So you think it's the temp changing causing the problems. Is there a better heater you would suggest

 

[twilliard]

I do not see it to be a water chemistry issue. (your GSP are happy)
I use the truetemp controller with a 300W titanium element

 

[saltyfilmfolks]

odd that the goni is doing so well thats usually the first to go.
can you post your parameters?
also are you running gfo?
what are you running in the canister?
how high is the ligh and what setting on your led.

it could be a combo nutrient light and low.