Ideal salinity?

[Mr. Fosi]

Missed it.

 

I so often miss the last post on a page.

[lakshwadeep]

Sure, but I got a whole lot more when I used to run at 35 ppt.

 

Where exactly is the salt creep? I have an old koralia that I recently added to increase water movement, and I soon found that the cord has a small groove that caused a lot of salt creep (in contrast to zero salt creep before) from apparent capillary action.

[Mr. Fosi]

On my current system? I have a bit on the teeth of my overflow, just above the rear spraybar and on a couple non-glued pipe joints above the sump. It builds slow and is really loose.

 

When I ran my 5.5g at 35 ppt, tight creep built up on everything... The AC70 spillway, the intake, the tank lip, inside the light housing (behind the glass), on cords that came out of the water... Everything.

[wombat]

Sure, but I got a whole lot more when I used to run at 35 ppt.

 

Was it a different tank? I can tell you from years and years of keeping many different style tanks at varying salinities that salt creep is a function of system design, not salinity.

 

But not to keep them in their natural light range?

 

Red herring, apples to oranges, etc. No MH light source mimics the sun perfectly. If one was available, I think we would all use it if we wanted to keep shallow water corals under ideal conditions.

 

I guess I don't see a big difference since we manipulate all other aspects of our systems to suit ourselves.

 

I think you'll need to define "manipulate" better if you want me to follow along with this thinking. Specifically, why manipulating a lower salinity benefits the corals (rather than you).

[Mr. Fosi]

No MH light source mimics the sun perfectly. If one was available, I think we would all use it if we wanted to keep shallow water corals under ideal conditions.

 

I guess maybe this is where we differ. I don't have any illusions about keeping corals under "ideal" conditions and I don't necessarily aim for that... And most others don't either. I know we can't replicate "ideal" or "natural" conditions and that's one reason why being 4 ppt lower than the surface of west Pacific doesn't bother me.

 

It doesn't matter whether a solar MH lamp existed, many people wouldn't use it because they want their tank to look s a certain way, rather than trying to attain some abstract "ideal" set of conditions. You already see this illustrated by the fact that many people here on NR (and elsewhere IRL) don't use "full spectrum" lamps like 67K or 10K. Of course, these lamps are not perfect emulators of the solar spectrum but they are a lot closer than the 14K or 20K lamps that most people use.

 

Now, you could argue that perhaps some people use these bluer lamps to emulate deeper depths and I am sure that some do but I would argue that a great many more people use them simply for coloration. Most people don't like the "yellow" look that the mid-K lamps generate and they like the blue/deep-blue and the fluorescence they generate in the corals.

 

Note that all discussions on here of what lamps to use involves color vs. growth and almost never does someone ask what is closer to being "natural" or "ideal".

 

I think you'll need to define "manipulate" better if you want me to follow along with this thinking. Specifically, why manipulating a lower salinity benefits the corals (rather than you).

 

I think I just covered that above. Also, I'm not arguing that lower salinity benefits corals, I am specifically arguing that it benefits the keeper without harming the corals.

 

I'm getting better results now than when I ran at 35 ppt. You can argue that the system is better designed. For example, that I have better lighting than I did then and you would be correct. You would also be supporting my argument. Perhaps lowering the salinity made things better. Perhaps it has little to do with salinity and instead the changes in flow regime, lighting and water source did it.

 

Argue all you like that the salt needed to affect a 4 ppt shift is negligible because it doesn't matter that much. I was just pointing out that people don't have to run at 35 ppt and higher to have good success and that if they are short on cash, this is an area that they can cut back and not damage their livestock.

[wombat]

For Fosi...can't download it at home but thought you might like to read it:

 

Hypo-salinity exposure on the coral Stylophora pistillata

 

Colonies of Stylophora pistillata were exposed to five salinity concentrations [39 parts per thousand (ppt), 32 ppt, 28 ppt, 24 ppt, and 20 ppt] that may realistically occur on a reef. Histological examination indicated an increasing severity of pathomorphologies associated with decreasing salinity, including increased tissue swelling, degradation and loss of zooxanthellae, and tissue necrosis. Pulse-amplitude modulated chlorophyll fluorimetry kinetics demonstrated a decreasing photosynthetic efficiency with decreasing salinity conditions. Cytochrome P450 levels were affected by even slight changes in salinity concentration suggesting that detoxification pathways, as well as several endocrine pathways, may be adversely affected. Finally, these studies demonstrated that hypo-saline conditions can induce an oxidative-stress response in both the host and in its algal symbiont, and in so doing, may synergistically increase oxidative-stress burdens. As with other types of environmental stresses, exposure to hypo-saline conditions may have long-term consequences on coral physiology.

[DashingAquatics]

"Colonies of Stylophora pistillata were exposed to five salinity concentrations [39 parts per thousand (ppt), 32 ppt, 28 ppt, 24 ppt, and 20 ppt"

 

Yes these conditions may be ideal for some coral however no tests have been done to include all species.

 

Also studies have been done that show neg effects on acro when expossed to red light and yet a favorite bulb amoung the hobby is Fiji purple.

 

Ntm a study has been done recently showing enhanced grown when exposed to 20000K vs lower K bulbs.

 

IMO the science in this hobby is much like the science in our day to day lives. Take coffee for example in some experiments it can prevent cancer and others it can cause it.

 

You can't read one study and make a definitive blanket judgement, you might as well take social lessons from Jerry Springer because its on TV.

 

My .02 cents, I can put the links in later if req for the studies I commented on however I'm on the other side of Canada then I live and don't have access to my documents.

 

Cheers.

[lakshwadeep]

Stylophora pistillata, in my limited reading, is one of the most common SPS that is researched, and results using it should be applicable to related genera.

 

The red light study (I think you're referring to the one by Dana Riddle) did not use acroporas, but it is important to note that there was a difference in what percentage of the light was in the red spectrum (i.e. using LEDs with very narrow ranges of wavelengths). Also, the fiji purple is not (IIRC) a bulb that has been used for many years, and I don't think any tests have been done to learn what it does to coral growth/color.

[Kraylen]

Don't listen to wombat guy never has a clue <3<3<3

[wombat]

"Colonies of Stylophora pistillata were exposed to five salinity concentrations [39 parts per thousand (ppt), 32 ppt, 28 ppt, 24 ppt, and 20 ppt"

 

Yes these conditions may be ideal for some coral however no tests have been done to include all species.

 

Also studies have been done that show neg effects on acro when expossed to red light and yet a favorite bulb amoung the hobby is Fiji purple.

 

Ntm a study has been done recently showing enhanced grown when exposed to 20000K vs lower K bulbs.

 

IMO the science in this hobby is much like the science in our day to day lives. Take coffee for example in some experiments it can prevent cancer and others it can cause it.

 

You can't read one study and make a definitive blanket judgement, you might as well take social lessons from Jerry Springer because its on TV.

 

My .02 cents, I can put the links in later if req for the studies I commented on however I'm on the other side of Canada then I live and don't have access to my documents.

 

Cheers.

 

Red herring about the lights. It has nothing to do with what we are discussing, despite the comparison.

 

If you have evidence that shows any corals grow better in depressed salinity, let's see it. Otherwise, it's just a guess/wishful thinking.

 

 

Don't listen to wombat guy never has a clue <3<3<3