Please help!! Lowering tank lights

[uutank]

Running 2 Zetlight zt6600 over my 180gallon, at a height of 12inches from the tank. Am not seeing growth on my corals though the colors are good. I strongly believe that lighting is the issue. Hence I’m adding two ati bulbs also to supplement the led’s. I’m also going to lower the height of my led’s. Currently my zets run peak 75% whites, 90% blues, 90% violets, 70% RGY.

MY QUESTION IS should I ramp down the intensity when I lower the lights or should I keep it constant, since my sps are 12 inches below the surface of water. I’m thinking of keeping the lights 6inches above the surface of water.

 

[Coralreefer1]

It is always a good practice whenever your plan on altering something in your tank to do it slow so acclimation time is optimal and stress time to your livestock is minimized.

 

[uutank]

It is always a good practice whenever your plan on altering something in your tank to do it slow so acclimation time is optimal and stress time to your livestock is minimized.

So you mean to lower the intensity right?

 

[uutank]

I would like some more suggestions on it.

 

[Ron Reefman]

I assume you don't have any PAR reading from your leds?

I don't think lowering the fixture by 6" will not bump up the PAR dramatically. PAR goes down pretty quickly when passing through water, but it does NOT go down much at all passing through 6" of air. If you weren't bleaching corals before, I don't think lowering the fixture 6" will do much. Given you are running your blues at 90%, I'd almost bet your PAR would go up more if you change the blue to 100% rather than lowering the fixture. But there is also the issue of just how good is the control of the leds. On a lot of fixtures the change from 50% to 60% is more that the change from 10% to 20% or 90% to 100%.

If or when you add t5 light, you will want to dial back the leds and do an acclimation run, depending on how many t5's you add.

Make a change and watch the sps corals that are the highest in the tank. Or you could try the 'canary in a coalmine' approach. Get a small frag of a red cap monti or any other inexpensive plating coral, and set it in your tank as high or higher than all the other corals. When you raise the light intensity too high, the red cap will start to bleach before any other corals. At that point, dial the power back a bit (10%-15%) and you should be good to go.

 

[uutank]

I assume you don't have any PAR reading from your leds?

I don't think lowering the fixture by 6" will not bump up the PAR dramatically. PAR goes down pretty quickly when passing through water, but it does NOT go down much at all passing through 6" of air. If you weren't bleaching corals before, I don't think lowering the fixture 6" will do much. Given you are running your blues at 90%, I'd almost bet your PAR would go up more if you change the blue to 100% rather than lowering the fixture. But there is also the issue of just how good is the control of the leds. On a lot of fixtures the change from 50% to 60% is more that the change from 10% to 20% or 90% to 100%.

If or when you add t5 light, you will want to dial back the leds and do an acclimation run, depending on how many t5's you add.

Make a change and watch the sps corals that are the highest in the tank. Or you could try the 'canary in a coalmine' approach. Get a small frag of a red cap monti or any other inexpensive plating coral, and set it in your tank as high or higher than all the other corals. When you raise the light intensity too high, the red cap will start to bleach before any other corals. At that point, dial the power back a bit (10%-15%) and you should be good to go.

Very helpful. Yes I don’t have a par meter and I don’t even intend on buying one it’s too costly for the work it does. Thank you I’ll just lower the lights without changing anything let’s see how it does. I’m adding t5 today itself, but it’s just 2 of those, and that too purple plus and actinic plus right now

 

[Ron Reefman]

Very helpful. Yes I don’t have a par meter and I don’t even intend on buying one it’s too costly for the work it does. Thank you I’ll just lower the lights without changing anything let’s see how it does. I’m adding t5 today itself, but it’s just 2 of those, and that too purple plus and actinic plus right now

I completely understand not having a PAR meter. I only have one because many years ago somebody did a group buy from Apogee and I got a $250 PAR meter for $175. Still pricey but a deal I couldn't pass up as I was getting into led fixtures in a big way back when they were very new.

Consider that the actinic plus and the purple plus t5's will still bump up the PAR by a fair amount. They don't look as intense to our eyes, but they really are. And anything with a shorter wavelength than blue is just closer to UV which can easily be harmful to corals and you can't even see UV! IMHO the t5 bulbs will add a lot more PAR than the lowering of the led fixture or even lowering it and increasing the blue channel to 100%.

Just be careful and watch those corals that are high in the tank for any signs of damage like bleaching.

 

[uutank]

I completely understand not having a PAR meter. I only have one because many years ago somebody did a group buy from Apogee and I got a $250 PAR meter for $175. Still pricey but a deal I couldn't pass up as I was getting into led fixtures in a big way back when they were very new.

Consider that the actinic plus and the purple plus t5's will still bump up the PAR by a fair amount. They don't look as intense to our eyes, but they really are. And anything with a shorter wavelength than blue is just closer to UV which can easily be harmful to corals and you can't even see UV! IMHO the t5 bulbs will add a lot more PAR than the lowering of the led fixture or even lowering it and increasing the blue channel to 100%.

Just be careful and watch those corals that are high in the tank for any signs of damage like bleaching.

Thanks Ron. But with the addition of purple plus and actinic plus won’t ramping up of blues to 100% will be an overkill? Also I run my whites at 75% is it good. My sps are 15inch below the surface of water, since I’ve loose aquascape so I don’t have high aquascaping.

 

[Ron Reefman]

You should be OK.

 

[tupes]

I'm going to lead a different route.

Yeah lighting could be the issue. Before messing with lighting, have you tested all of your elements in the tank? That could be a good possibility also.

 

[glb]

You can rent a par meter from BRS now.

 

[uutank]

I'm going to lead a different route.

Yeah lighting could be the issue. Before messing with lighting, have you tested all of your elements in the tank? That could be a good possibility also.

Yes params are all fine

 

[uutank]

You can rent a par meter from BRS now.

Not in my country brother

 

[ashleyt]

Running 2 Zetlight zt6600 over my 180gallon, at a height of 12inches from the tank. Am not seeing growth on my corals though the colors are good. I strongly believe that lighting is the issue. Hence I’m adding two ati bulbs also to supplement the led’s. I’m also going to lower the height of my led’s. Currently my zets run peak 75% whites, 90% blues, 90% violets, 70% RGY.

MY QUESTION IS should I ramp down the intensity when I lower the lights or should I keep it constant, since my sps are 12 inches below the surface of water. I’m thinking of keeping the lights 6inches above the surface of water.

You could also try placing your corals higher also check your water flow. We have wave makers in ours and some corals take different intensities..
As for lights we have the kind that have both led and normal lights so we can dial it down using knobs.

 

[IslandLifeReef]

One thing that I haven't seen mentioned is that LED's tend to be more directional than T5's or MH's. Unless you have a diffuser on the lights, you may risk having "hot spots" in your tank where there is to much light. Even with a diffuser, this can happen with LED's. The closer you move LED's to the water, the greater the risk of uneven light spread.

 

[uutank]

You could also try placing your corals higher also check your water flow. We have wave makers in ours and some corals take different intensities..
As for lights we have the kind that have both led and normal lights so we can dial it down using knobs.

Can’t move corals up I’ve a loose aquascape so I’ve already kept them as high as I could balance the rocks without the risk of them tumbling. So presently the sps are 12-15 inches below water surface that’s the topmost part of my tank

 

[uutank]

One thing that I haven't seen mentioned is that LED's tend to be more directional than T5's or MH's. Unless you have a diffuser on the lights, you may risk having "hot spots" in your tank where there is to much light. Even with a diffuser, this can happen with LED's. The closer you move LED's to the water, the greater the risk of uneven light spread.

True that, but they’ll still be 6-8 inches higher than surface of water