Flow and dead spots

adtravels · Jan 24, 2018

Dear all

I reckon this is a flow issue but let me know your thoughts.
Mt Params are pretty rock solid and the tank is 1 year old.
My ati ICP test was good for all major things, I adjusted the potassium slightly.

salinity 35
alk 7,8
cl 430
Mag 1300
potassium 400

Most of my stuff is frag grown and the two pieces with issues were grown from frags they are now decent sized mini colonies. Right at their cores they both have dead spots with algae growing in each (hardly noticeable at a glance). I have a tunze 1073.040 return and two mp40wQD on either end of the 90 gallon system

In the video it id the sps colony dead center at 20 seconds with sits under the vortech at one end and the purple colony back right at 1.45. pretty much under the other vortech.
All the other corals don't seem to have these dead spots. Interestingly both were moved midway through their growth due to a rescape. I am thinking of adding more flow in the middle of the tank on the back wall to cope as the tanks matures and hope the dead spots recover and the corals adapt.

Moonfruit777 · Jan 24, 2018

Can't really see anything wrong on the Video. I'd say leave them where they are right now and don't change anything.
If the dead spots are covered in algae they are not new/fresh. Just keep an eye on them and see if the dead area increases!
The cause could easily be connected to flow- just some detritus or sand that may have landed on the coral and was not removed fast enough.
I once had a hermit crab "stuck" on a coral and until I noticed and removed him the tissue underneath was bleached. ¯\_(ツ)_/¯
But seeing those polyps on the millepora it looks there is plenty of strong flow in the tank.

I say no need to worry if the damage does not increase- if your tank conditions suit the corals they will for sure get over it

adtravels · Feb 18, 2018

I sti have this issue and it has got worse, I have added a third mp40 today to see if it hels but I am starting to worry a little!

adtravels · Mar 18, 2018

I was probably wrong about this, high copper on my ICP may well have been the issue as with WC and some chemipure the recession has stopped. I was slurry dosing trace elements from Fauna Marin, this may well have been the issue. A kind member here put me onto that.

Lighthouze08 · Mar 23, 2018

video not playing

Rakie · Mar 26, 2018

Also how high is "high"? Lots of people have elevated copper in their tanks according to ICP results yet their tanks are fine. Additionally, almost every single "Color booster" acro potion has copper in it, to make corals shed their zooxanthellae and lighten up, showing their real color.

adtravels · Mar 26, 2018

Cu @7.6 PPB

Graffiti Spot · Mar 26, 2018

Slurry dosing them?

adtravels · Mar 26, 2018

yes I was but no longer

jda · Mar 26, 2018

The dangerous forms of copper bind to aragonite and organics (and skimmed) and are quickly rendered harmless. Zinc is also used in the color enhancers since it is more effective, but it is true that copper is an ingredient... but there are many, many forms and I do not know which are used.

I do not like too much flow that my sand blows around. I would use a gyre and 2 MP40s, if those are all that you are considering. MP40 might move a lot of water, but it is too wide and not all that effective, IMO. I prefer Tunze or even AquaMedic Ecodrift better. I only use a pair of 6200s and wavebox on my 240 and it is plenty of flow and I have colonies.

The video does not work, but is your issue from light shadowing? Low flow will affect growth patterns, but should not kill colonies in the middle unless debris can settle.