par settings

[cluanar]

So I have had my tank for about 17 months and although numbers have been good I cannot get corals to grow and in many times survive.

I have two (2 puck ) AI vega lights and even and w 5 all blues 20 it looks extremely bright.

I decided to rent a par meter and at the highest point of the day did a measurement and found that the bottom had a 15 par and the top 30 par.

I could not have imagined it would be that low since to the eye it was so bright.

I guess then I need to satisfy the par needed despite what the eye wants?

Thanks

 

[redfishbluefish]

Something is not right. AI Vega easily puts you in the 500 - 600 range, or higher, at the surface. Either the lights aren't working correctly or the PAR meter was off.

 

[cluanar]

Current settings and par
lights 10 inches from water

in a 90 gal 31 in from sand bottom

Here is a pic that shows how bright the tank looks.

White 20%
Red 4%
Green 7%
Blue 75%
D-Blue 75%
Royal 75%

Par at water level 270 ( above the water its 400, just submerged 270 )

Mid 120

Sand 30-50

Seems too low still but looks super bright in tank.

 

[cluanar]

Current levels with these settings


White 20%
Red 4%
Green 7%
Blue 75%
D-Blue 75%
Royal 75%

 

[Aardvark1134]

par meters are for the most part garbage even the several thousand dollar ones are often off by as much as 35%.

 

[o00brandon00o]

par meters are for the most part garbage even the several thousand dollar ones are often off by as much as 35%.

@Aardvark1134 Source?

 

[Aardvark1134]

There was a BRS video a few weeks ago... the industry standard one was off by 35% and had been for years and noone noticed...the next most expensive they tested was misreading by about 20% and had to be sent back for an update...the 2 cheapest they tested were only close to the right # because the part they were under reporting was off by about the same amount as the part they were over reporting. Short version all 4 were garbage and not a useful source of information. They admitted since there several thousand dollar one was off by 35% that all their old par videos were also off by 35% as that is the one they had used for all of them.

 

[saltwaterpicaso]

for each meter on the market there is a correction percentage to be calculated in because the meters have a hard time with the blue spectrum

 

[Aardvark1134]

it's more than that. Some also over report the yellow by almost 40%, some don't work at angels, some don't work correctly underwater even though they say they do...and some have software mistakes that make them read wrong for years before anyone notices... here have 4 examples

 

[Oldreefer44]

my guess is that is something other than the lighting. I would have your water independently tested. In my experience, we tend to look at everything but the most basic and that is consistent, good water quality.

 

[cluanar]

My water tested fine.

my guess is that is something other than the lighting. I would have your water independently tested. In my experience, we tend to look at everything but the most basic and that is consistent, good water quality.

 

[Aardvark1134]

Have you tried something almost impossible to kill like GSP or Xenia ? Maybe a Zoa? Or are you trying SPS? Have you tried putting something up high in the tank or just down low?

 

[cluanar]

Have you tried something almost impossible to kill like GSP or Xenia ? Maybe a Zoa? Or are you trying SPS? Have you tried putting something up high in the tank or just down low?

I get $5 ZOA frags from a close by reefer and most everything eventually closes and hardens over. Brought my water to a lfs and they said everything is fine. I changed my ligth settings to:

W 25
Red 13
Green 11
Blue 85
D-Blue 85
Royal 85

Now i get 390 across most of top 150-175 mid 50-90 sand bottom. Tank looks so much brighter than before but if that is the par i need then my eye will adjust.

 

[cluanar]

What par do i want my Red Gorgonian.

 

[Aardvark1134]

LFS only test the basics. You might want to get a ICP test run. They aren't cheap to run but then neither is loosing coral after coral. If it says it's not your water then it's not. You would only need to run it once to find out if water is the issue.
https://www.marinedepot.com/ICP_Wat...ntent=CV1691&gclid=CNy5_PGE2-ICFYu4wAodRd8JgQ

 

[o00brandon00o]

par meters are for the most part garbage...

@Aardvark1134 you watched the entire video you posted and came to that summary conclusion to share with the OP? What other system(s) do you have experience with to measure photosynthetic active/usable radiation?

 

[Aardvark1134]

The best system is to stick a couple corals in there at different height and adjust more or less light on how they act then fill your tank. A par meter that is way off trying to help you meet another persons # that may have been way off the other direction is useless. The only way I would trust a par meter #s at this point is if I went to someones successful tank and measured the par and then went to my tank with that same meter (not same model but same meter) and measured it. Even then you run into the issue of what matters is pur not par. So really you would also need to be measuring the same type of light source as well. In short par/pur meters may be a great item in about 5 years but right now they are not something to be trusted.

 

[cluanar]

So I am going with the following settings

W 20
R 15
G 15
B 85
D B 85|
RB 85

Even though those numbers seem high to me and tank looks bright par shows okay.

Par readings show
top 1/3 250-375
mid 125-200
bottom 35-80

Seem okay?

 

[Aardvark1134]

You will know when you add corals. They look different when they are not getting enough vs too much light.

 

[cluanar]

A zoa I thought gone is popping back up!!!!! yaaa