Why is this happening???

[kleach]

Out of no where things in my tank have started to die. I lost one colony about a month ago, another colony 2 weeks ago and another colony 2 days ago. I'm starting to notice what looks like burnt tips on some of my other colonies. I haven't added anything to the tank in the past 2 months, so I'd doubt it was any type of pest causing it. Nothing seems to be on the skeletons either.

Ammonia 0
Nitrite 0
Nitrate 5
Mag 1420
Alk 8.1
Cal 430 - I know its low
pH 8.2

Any insight? Have auto top off and chiller. I did switch to Bulk Reef calcium, mag and alk supplements from Red Sea about a month ago. Maybe that's it?

Thanks

 

[pecan2phat]

What test kits are you using & have you tested your phosphates?
Also what temperature and is it steady or large swings? (This can happen when you have a big offset on the chiller)

 

[Reefist]

430 on Ca is not low check salinity

 

[kleach]

Forgot to say Salinity is 1.024.

I'm using a Ranco controller for the chiller to keep it at a 1 degree differential. I keep it at 78 and when it hits 79, it turns the chiller on till it hits 78 again.

I was using API for ammonia and nitrite, Salifert for nitrate (also did the API and got the same results), and Red Sea for Ca, Mg and Alk. Refractometer for salinity. I have the Red Sea phosphate pro test but forgot to do it today.....I also hate that test because I can't tell the colors apart.

I've been dosing with CoralAmino, Phols Xtra, and fauna marin color enhancers. Also have been using Special Blend to help with a red slime issue I've been having, but that has since been taken care of.

Thanks for the responses and please let me know what it might be!

 

[MIKE NY]

Are just the SPS effected or is it any other species of corals?...losing over night or a few days? Are they colonies you have had for a few years grown from frags or recent additions within a few months? doubt it's phos or nitrates..SPS usually brown out first from that or pests which I usually see loss of color and PE first....possibly either, as mention a temp swing or an alk swing...burnt tips are usually an indication of that...how are you dosing alk..manual, doser, reactor?

 

[kleach]

Just tested my phosphates and they are .02
Also rechecked my Alk and its 7.6 - But, I could have also misread the 8.1 it was yesterday because I feel like the Red Sea Alk test sucks. Also, these colonies have survived much worse Alk swings than that.

It seems that just the SPS are being affected. The colonies have been in the tank for at least 7-8 months and have been doing great. I think the first one I lost was because another SPS frag touched it and stressed it out, but the other 2 were a mystery. The loss is happening over a few days. In fact, the last colony I lost I decided to frag the crap out of it to try and save a few pieces...so far only 2 frags of it have lived.

I just started using a Bubble Magnus to dose in order to make the levels more stable. I'm testing every few days and adjusting the amount dosed because Bulk Reef's calculator for how much to add was way off from my daily consumption.

As far as losing color....I didn't realize how gorgeous my colony of Aqua Delight was until a week or 2 before losing it. The colonies are fully colored and with full PE as they STN. I seriously doubt it was a temp swing because the chiller is being controlled by a temp probe keeping it at 1 degree differential.

Thanks and keep any ideas flowing if you can.

 

[kleach]

Also forgot to mention that the majority of the colonies are doing extremely well. I have a millie that is exploding with growth, a strawberry shortcake frag that after 6 months finally colored up and is growing very nicely, a red planet that has lots of growth. Really only 2 of my colonies look like they have the burnt tips, but after losing 3 colonies I figured I'd reach out to you guys.