No PE on SPS corals

[pammy]

I'm hoping you can help me Kevin.

I have a 53 gallon tank with a 7 gallon sump that has been set up for 10 months (my first salt water tank). I bought my first SPS corals. Bought 6 Millipora frags about 3 or 4 weeks weeks ago. 5 from one reefer, 1 from another. Not much color on any of them in my tank, and not really any PE. I thought it might be flow, so I added a 2nd Tunze Nanostream 6025 (had one in there already, and a MJ1200, and a Eheim 1260 for return pump). That gives me about 35X flow now in my display (was about 25x before adding the 2nd tunze). The one milli that had halfway decent PE, has almost none now that I added the new powerhead. I've peaked at night, and don't see any PE then either. I do know, that I just checked my levels, and my Nitrates and Phosphates were at 0 for several months, and right now, I have Nitrates at 5, and Phosphates at .1
Would that be enough to cause a problem with PE and color?

For lighting, I have one 150w MH 10k Elos bulb and four 24w T5's
2 super actinic and 2 blue+). MH is on for 5 hours and T5's are on for 10 hours. Maybe I need to extend the photo period?

I also have a Coral Beauty. I just saw him take a quick nip at one of the millis yesterday. He doesn't seem to be nipping as in trying to take a bite, just trying to taste it like he does to any and all surfaces in the tank. Maybe he's nipping more often and I haven't seen it. But like I said, I don't notice any more PE at night when the lights have been off for several hours.

I know the mother colonys in the reefers main display tank had super PE when I bought the frags. Frags were in a frag tank though, and I'm not positive, but I don't seem to remember them having much PE in his frag tank or any more colorful in his frag tank than they are in my display. They don't seem to have browned out, just not showing any color under my lighting. The guy had the most beautiful tank (I think a 280g) I've seen, and was spotless as you could imagine, with great colors, so he obviously knows what he's doing.

I'm not sure what I should try next, now that I added more flow.
Just an FYI.... I had a sun coral and a duncan that are doing beautifully and growing more heads, a frogspawn that is far away from all other corals that's doing ok, one smaller rock of zoos that is doing good, one small rock of mushrooms that's doing ok. I had a leather that I brought back to the LFS months ago after reading about the chemical warfare they can cause, and decided to keep away from softies after that.

Tank Parameters:

SG 1.025
Temp: 80f
Nitrites and Ammonia: 0
Nitrates: 5
Phosphates .1
Calcium: 410
Magnesium: 1230
PH: 8.3 day, 8.1 night
Alk: 8

Any suggestions?

Thanks, Pam

 

[kevinpo]

Hello,
Phosphate should be less than .03 and nitrates 0ppm. A small phosphate reactor would work well on your size tank. A refugium with macro algae (like Chaetomorpha) run on a reverse photo period would help to keep the nitrates at 0. I would also increase my halide photo period to 8-9 hours.

HTH,
Kevin

 

[pammy]

Thanks Kevin. Do you think it's more likely the Phosphates and nitrates rather than the Coral Beauty that is causing the Polyps not to extend? If it was the Coral Beauty, should I see polyps extending when the lights have been off for hours (I don't) ? I tried catching him a few times to return him to the LFS, but he's a quick bugger. Again, I don't see him nipping, as if he's going to take a chunk out of the SPS, just a quick fly-by nip, like he does to every inch of rock and glass in the tank. Not sure if that would be enough to aggrivate the Milliporas to the point of them not extending their polyps at all.

I'll take your advise on increasing the MH photo-period.

Any recommendations for a good phostphate reactor for a system my size (53g with 7g sump), and what type of media do you put into it?

I've tried Chaeto twice in my sump and it didn't do well. I do have a large bit of Dragons Breath growing on my live rock in the display which I cut back every 2 weeks or so (see pic below). That sprouted on it's own on my live rock. I just tried supergluing some of the Dragons Breath to a piece of Rock Rubble, to see if a second colony would grown (figured twice the amount, would be twice as good for nutrient export). It is growing on the frag. Not sure if the Dragon's Breath is as good as Chaeto for nutrient export, but it sure is a whole lot prettier!!

Nitrates and Phosphates were at 0 for a couple months. I tried to think of what changed to see an increase to .1 for phosphates and 5 for nitrates. I do have more fish (7) and I have been feeding them Forumula 1 flakes for a 2nd feeding a day, and frozen mysis and other frozen foods for the main feeding. I cut out the flakes about a week and 1/2 ago to see if that would make a difference, and I also FINALLY got my skimmer working correctly. Could never get it to skim a whole lot, but got that figured out, so it's cranking now. I'm hoping that makes a difference too. Thanks Kevin! Pam

Hello,
Phosphate should be less than .03 and nitrates 0ppm. A small phosphate reactor would work well on your size tank. A refugium with macro algae (like Chaetomorpha) run on a reverse photo period would help to keep the nitrates at 0. I would also increase my halide photo period to 8-9 hours.

HTH,
Kevin

 

[kevinpo]

Hello,
The Two Little Fishes reactor and media or similar would work well. You can easily catch the Coral Beauty with a small hook and a piece of freeze dried plankton on it.
I would not use the flakes. A properly working skimmer will help a lot. Chaeto does best with VHO, HO-T5, PC, or halide lighting.

Regards,
Kevin

 

[dailydriven911]

I would go w/ a 250w mh lamp instead of the 150. Also increase the flow to at least 40-50x turnover. Like Kevin said get the phosphate level as close to zero as you can.

 

[packer]

I concur also, flakes are a bit "dirty" compared to other foods. I use a very small bit every couple of weeks just because I like to feed some of everything for the best shot to give the fish all they may need. While your nitrate is at 5ppm thats not really bad at all. Yes we all strive for perfection, but I have seen many tanks with decent SPS with 10-15ppm. The phosphate reduction via TLF reactor will be a big plus. Test kits are not that great at showing true phosphate and many do not even show different kind of phosphates at all, so they may well be higher then you are showing with a test kit.You might want to also get your Magnesium up to around 1300, and also raise your Alk a little bit. These adjustments will help all things a little.

I also am guessing that the frag tank did not have the best parameters as the display tank. Most I have seen do not, unless they are plummed off the same sump. Some of my SPS frags have taken even up to 2 months to adapt to my tank, so if no RTN then your already half way to success.

The Coral Beauty is probably your main problem. He is no doubt doing more damage than you have seen. The fact you have seen him nip is enough to know that he is up to it, and also probably takes a lot more then you see. Even "some" nipping is not good. Good luck catching him!

 

[Skimmy]

imo, i think you need to get your alk up to more like 9-10 as well as 0 phos, and 0 nitrate. any of the really nice millies and monties i had would never really color up all the way with alk that low. i'd rather have alk a little higher and calcium at like 370-390 instead of 410-420.

and it looks to me like you have an elos system 70...correct?
if this is the case do you have the elos 500 skimmer? and if not, which skimmer do you have?

oh yes, and ditto on increasing your daylight period... to more like 8 hrs

 

[pammy]

Hi Skimwisperer. You're close. It's a Elos System 80, and I do have the Elos NS500 skimmer.

What product would you all recommend to raise my alk? And how high should my light fixture be above my water line? Currently, it's 10" above the water line, and 15" above the Millipora's.
Thanks! Pam

imo, i think you need to get your alk up to more like 9-10 as well as 0 phos, and 0 nitrate. any of the really nice millies and monties i had would never really color up all the way with alk that low. i'd rather have alk a little higher and calcium at like 370-390 instead of 410-420.

and it looks to me like you have an elos system 70...correct?
if this is the case do you have the elos 500 skimmer? and if not, which skimmer do you have?

oh yes, and ditto on increasing your daylight period... to more like 8 hrs

 

[pammy]

Hi Packer. Thanks for your input. I just ordered the "Fish Corral" at DrsFosterSmith to try to catch the coral beauty. I have a feeling you're right and he is doing more damage than I realize. I just ordered the phosphate reactor too. What does it look like when corals start to get RTN? Do you start seeing the white skeleton? I don't see any of that at all. Actually looks like there is some new growth on the tips. Just no PE and no color. Thanks for all the tips!!
Pam

I concur also, flakes are a bit "dirty" compared to other foods. I use a very small bit every couple of weeks just because I like to feed some of everything for the best shot to give the fish all they may need. While your nitrate is at 5ppm thats not really bad at all. Yes we all strive for perfection, but I have seen many tanks with decent SPS with 10-15ppm. The phosphate reduction via TLF reactor will be a big plus. Test kits are not that great at showing true phosphate and many do not even show different kind of phosphates at all, so they may well be higher then you are showing with a test kit.You might want to also get your Magnesium up to around 1300, and also raise your Alk a little bit. These adjustments will help all things a little.

I also am guessing that the frag tank did not have the best parameters as the display tank. Most I have seen do not, unless they are plummed off the same sump. Some of my SPS frags have taken even up to 2 months to adapt to my tank, so if no RTN then your already half way to success.

The Coral Beauty is probably your main problem. He is no doubt doing more damage than you have seen. The fact you have seen him nip is enough to know that he is up to it, and also probably takes a lot more then you see. Even "some" nipping is not good. Good luck catching him!

 

[kevinpo]

Hello,
Rapid Tissue Necrosis (RTN) happens in a few hours to one day. Bright white skeleton is exposed and prompt action is required. For a 150W halide 6" from the water will really help to utilize the bulb better. You are getting about 30% of the intensity at 10" compared to 6".
http://hyperphysics.phy-astr.gsu.edu/hbase/forces/isq.html

Regards,
Kevin

 

[packer]

The good part about RTN: It is pretty apparent that you have it and is recognized easily.

The bad part: It comes on quick and will take the coral out in only a day or two ( unless its a huge piece)


So it sounds like you dont have RTN or your coral would be skeleton by now. Most times RTN will start at the base and work its way up.

Start your reactor off slow, either with less than half the recommended amount of media or a very slow flow thru the unit if you put in the full amount of media. You do not want to shock your system by dropping the phosphate all at once. Also watch for a possible drop in Alk with the media.

Do you run any carbon also?

 

[dnjan]

For a 150W halide 6" from the water will really help to utilize the bulb better. You are getting about 30% of the intensity at 10" compared to 6".
http://hyperphysics.phy-astr.gsu.edu/hbase/forces/isq.html

Kevin - you should know better. That link is for a point light source. A MH bulb with a decent reflector does not follow that law, as more than half of the light hitting the water surface comes from the reflector at close to 90-degrees to the water surface. So no dispersion for that light. For the light that comes directly from the bulb, you also have to consider angle of incidence (with lower penetration of the light when the angle decreases below perpendicular).

So, if you have a decent reflector, the effect of the distance the bulb is above the surface of the water is practically negligable.

 

[kevinpo]

Hello,

So, if you have a decent reflector, the effect of the distance the bulb is above the surface of the water is practically negligible.

Metal halide lighting is a point source light and follows the law. The distance from the water is critical as shown in this graph by Sanjay. Notice the peak μmol/sec/m2 (PPFD) range between 6 and 9" is (3000 vs 800). This is a decrease of almost 4 times. Reflectors act as a focus device as shown by the change in the light distribution as the reflector is raised. The reflector is a PFO parallel type.

Here is a link to the entire article:
http://www.advancedaquarist.com/issues/mar2003/feature.htm

I am hoping to have Sanjay here in Spokane to give a presentation along these lines July 12th, 2008.

Regards,
Kevin

 

[dnjan]

I believe that those measurements are in air, not light that has penetrated the water surface.

Also, I said a decent reflector (implying close to parabolic). With a parabolic reflector, the light comes down at an angle of incidence of 90-degrees to the water surface. No spreading.
The "decrease in intensity as a squareof the distance" is simply taking into account the spreading of the light.
True, a MH bulb with no reflector can essentially be considered a point source. But with a decent reflector, more than half of the light hitting the water surface is reflected, and is therefore not dispersing. (no inverse-square effect). And the light that does come from directly from the bulb has the added problem of refraction at the water surface (as the angle of incidence decreases from 90-degrees).

 

[Scooterman]

Weather the reflected light entering the water or the light from the lamp that enters the water both should at that point have the same characteristics right? So refraction should occur when any of the light hits the water, reflected or not. You will get angle of incidence variances around the radius of the length of the lamp & the reflected light. So once in the water your getting so many angles of incidence it would be crazy & difficult to even measure accurately but mathematically you could figure it out, to me it would look like lines of light entering the water from all above directions almost. Also I thought the better reflectors are Designed to disperse some of the light & not throw it all back close to 90 degrees, that would almost be counter productive & very point source, my reflectors spread at least Part of the light out as I go higher off the water surface.

 

[dnjan]

The biggest difference between direct light and reflected light is that once you move out (horizontally) from under the bulb, but still under the reflector, the angle of incidence for the reflected light is closer to 90-degrees, while the angle of incidence of the direct light is decreasing the further you go out. So, as you move out from directly under the bulb, a greater and greater percentage of the light actually entering the water is coming from the reflector.
Since we are mostly interested in lighting an area significantly larger than the size of the bulb, the reflector becomes overwhelmingly important. Thus the greater importance of having correct reflector design and lessor importance of distance above the water.

Kind of makes sense when you hear (read of) people really praising the amount of light they are getting from luminarc-III's, and why they are willing to pay for those reflectors.

 

[Scooterman]

I have those reflectors & by lowering the lights to 6" off the surface from 9.5", I noticed a great change within the tank from Observation, one the corals & two the amount of light inside compared to having them mounted higher. Obviously this isn't all because of air space because of the lowered incidence angle gets more light into the tank. If I had a meter it still wouldn't help here because your accumulating more light by two means & testing would require the series done with no reflector vrs height & air & compare that to adding the reflector but somehow remove the air gap to be a true test. How you do that last part, I don't know but there IMO is benefit of getting that lamp closer to the water, with or without the reflector. I agree that it wouldn't be as much in a good reflector or any really but how much you gain by having less air travel is the difficult thing to measure without math, I can't believe it isn't significant as you make it seem comparing to the reflectors?
Can you agree that is true?

 

[dnjan]

Air travel is almost nothing compared to water travel.

Take a look at Sanjay amd Marks

and scroll down to the section on the luminarcIII reflector.

Look at the intensity directly under the bulb for heights of both 6 and 12 inches. I read PAR values of approximately 2,400 and 1,050 respectively for those two heights. Just a bit more than double, not nearly four times as would be predicted by the "inverse-square rule".

Now look at the intensity at 9" out for the same two heights. (Asking a good lighting system to illuminate an area of at least 18" by 18" is a fairly reasonable expectation.) I read intensities of between 400-400 PAR for both heights. No difference in intensity even though the distance between the bulb and the lightmeter was doubled!

So, yes, directly under the bulb there is some difference in light intensity from different heights. This difference, however, is nowhere close to that predicted by inverse-square. Move out a bit horizontally, and the angle of incidence effect takes over. By the time you are looking at illiminating a reasonable area of your tank, height is practically inconsequential.

 

[Scooterman]

I thought that inverse square rule was for just the light, no reflector. It is apparent that your gain from the reflector is very important & on a scale that making the comparison to a lamp with no reflector or just air your not getting the results as mentioned but how would the inverse law work on just the lamp?

 

[dnjan]

In my original post to this thread (Post #12), I was kiddingly chastising Kevin for trying to apply the inverse-square law to a MH over an aquarium (which I assumed included at least some form of reflector).

With no reflector, the inverse-square law applies while the light is in the air (actually, the law is for light in a vacuum, but for the distances and measurement precisions we are talking about, it is good for air as well).
However, when the light hits the water surface, the angle of incidence becomes important (the inverse square law looks at the light intensity on a plane perpendicular from the line of light from the bulb). So, the further out horizontally you get from directly beneath the bulb, the more the angle of incidence deviates from 90-degrees and the lower the percentage of light hitting the surface that actually penetrates (rather than getting reflected back up by the surface). For bulb alone, when not directly beneath the bulb, the intensity of light actually entering the water decreases more rapidly than predicted by the inverse-sqare law. The amount depends on how far out you are horizontally. Since none of Sanjay's reflector tests show decreases in intensity that high, it is easy to conclude that the reflector outshines the bulb itself!

Note - none of this is considering absorption of the light (by particles, etc. in the air). Even where you are at, the humidity isn't high enough to cause a measurable light absorption for the air distances we are talking about. Absorption in water is a different matter, and is measureable for aquarium-depth dimensions. Particulates and even disolved organics can significantly increase light absorption in the water, resulting in reduced intensities at the corals. One of the reasons why improved skimming and/or the use of carbon can improve coral coloration.