What is the difference

[Koda2007]

I was in a LFS today and a man was asked if his sps corals were dying from the base or from the tips. WHY????.
What is the difference. ????

Could someone explain to me.

Thanks

[framerguy]

Bleaching usually occurs from the tips down, RTN and STN usually starts at the base. Each sickness has different remedies. (Actually not much can be done for RTN). That's my experience.

[Koda2007]

Thanks Framerguy.

One of the reasons I was asking was that I lost a few acro's from the tip down a while ago. I thought that bleaching would be the obvious answer to dying from above. The problem i have is that they were originally kept at high tank level under 400watts 14000k MH
My tank is 300watts 14000k + 110 watts T5's with guismen 60% 6500K and 40% 22000k bulbs. I would presume my lighting is inferior or on par with the LFS therefore I believed that bleaching was not the answer in my case. Is there anything else that could cause dying from tip down.

All my parameters were fine triple checked at 3 different LFS

Thanks

[sasquatch]

possibly your water is a lot cleaner than where they came from, that would increase par

[mps9506]

If you already know how to tell the difference please disregard
There is a major difference in bleaching and RTN/STN. If you look carefully at the acro colony it will be obvious which on it is, regardless of it starting at the base or the tips. this will give you a baseline of what steps should be taken next IME.
Bleaching even after it occurs can be reversed, healed whatever you wanna call it. If your acros still has tissue and you can still see the polyps but it looks white, it is bleaching. this can occur from the top bottom middle etc. Often times the underside of your colonies that don't receive light or good water flow will bleach and die off this may or may not be preventable. Some of it is natural as the coral keeps growing outwards and upwards.
If the entire colony is bleaching you can probably attribute it to stress caused by any of many factors such as large temperature fluctuations, major hcanges or swings in pH, lighting etc. This is why sometimes colonies will bleach shortly after being added to a new aquarium. There might be a significant enough difference in light, temp, pH or something else that will cause it to expel it's zooxanthellae.
A safe bet would be to either move it lower in the tank or decrease your lighting for a period of time to help acclimate the coral to your tank conditions. As well as ensure your tank temps are not fluctuating huge levels in a short period of time and make sure your water chemistry is near NSW levels.

RTN/STN is a whole nother creature
I can't tell you exactly what causes it. Stress, parasites, predation, disease all appear to be viable factors in tissue necrosis of acros. I would think it occurs more often than not in wild colonies that are moved into aquariums than second or third generation fragments. Although I have no proof whatsoever.
Tissue necrosis, is just that, you will see the tissue floating off of the coral as it dies. It can occur quickly (RTN) or slowly (STN). It's painful to watch and will make you feel helpless when it happens. You can try to frag pieces of the acro that are still healthy and hope those sections hold on.

As far as the conditions you describe. Moving from higher to lower light doesn't usually result in bleaching. Maybe some browning out or maybe less intense or maybe even more intense coloration.
you mention your water parameters checked fine, but I'd be interested in what the actual numbers are for Ammonia, nitrites, nitrates, pH, Calcium, alk, SG and temp.

[Koda2007]

Thanks mps9606.

At the time of my losses my parmameters were as follows

Sg 1.026
Amm o
Nitrite 0
Nitrate 0 - 5ppm
Phosphate 0
Ph 8.2
Dkh 9
Calcium 480
Mg 1400
As mentioned triple checked. One LFS owner ( respected ) even came to my house as he did not believe I was having probs with all the water tests he did and nothing showed. He said that he would be chuffed with my reef and was at a loss as to why my sps corals were dying.

Weekly 10% water change with Red Sea Pro and R/O water.
Evap tpooed off with R/O water nd Kalk. No other additives used.

Definately not RTN

I apologise for not answering sooner but in bed ( uk ) when you posted then been out with family.

Thanks again for input.

[prow]

could it be, na, well maybe its red bugs???

[framerguy]

could it be, na, well maybe its red bugs???

NNNNNOOOOOOOOOOOOOOOOO!!!!

[Koda2007]

100% not red bugs.

I have some pictures saved of the corals and how they receaded from the top down. I will try to dig them out tomorrow and post them.

00.20am here in the UK, goodnight to everyone and thanks for your help

Koda2007 ( Neil )

[prow]

pics will help. now that i put red bugs in your head, sweet dreams

[kathywithbirds]

following...

what's "chuffed" mean?

[prow]

chuffed=proud or very pleased~its a british thing

[Koda2007]

Good morning to you all.

Well impressed prow with your 'british thing' dialect. I will try not to use english slang again, I sometimes forget I am not on a UK forum.

I am trying to find photo's as stated but having a very busy day.

I earlier stated that it was Acro's that were dying from tip down it was infact Monti's aswell.
I have been keeping all types of fish for 30 years and started keeping marines again after a 15 year absence. The reef had been set up about 3 years with a few fish and softies. I felt I needed to do this as reef keeping had changed that much in 15 years, it was like just beginning again and I needed to find my feet again.
Anyway after 3 years of softies growng out of my reef and not losing 1 single fish or invert I wanted a bigger challenge, hence Monti's and Acro's. A lot of softies were exchanged for fragged Monti's and Acro's. All opened up well ( polyps ) and appeared to be doing fine for 3 - 4 weeks and then they started receeding from tips down. At this stage water checked at LFS. No probs.
Put extra carbon in. Over the next few weeks they continued to receed to the point of no return.
Left reef with no Sps for a number of months and did 15% water changes. Checked water for every posssible thing you could test for. All tests perfect.
Tried some new frags of Monti's and Acro's which did well for a few months and then the same happened again.
Water checked again and this is when the owner of a LFS came to inspect setup and as already stated was well impressed and could not understand the problem. When I am ready the LFS owner is givng me a couple of Acro's and Monti's free of charge but I do not want to kill any more corals. I would like to get to the cause of the problem first.

A few other facts

Reef is 120 uk gallons
Nitrate reductor ( large one )
Deltec mce 600 protien skimmer
Aqua medic calcium reactor
phosphate reactor
small sump with cheato and other macro algae
coraline algae growth is unbelievable

[lcstorc]

What do you have for lighting? That's the only thing I can think of based on the information given.
Did they test your alk, calc, and mag? If those are out of balance many things don't do well. The hard corals particularly need these in balance.

[Jason25]

I have also heard of corals bleaching due to water temps. They use their defense machanism of expelling algae to try and cool themselves down.