How to "Safely" Increase Light Intensity

[cdw79]

Awhile back I splurged on a nice Indo Gold torch, and the seller said he's noticed they keep their color better in brighter light and can fade a bit in lower light. I bumped up my Hydra 32's about 5% per week over about 3 weeks, but had three different corals bleach on me (I don't recall my exact parameters at the time but having double checked my own readings with my LFS and gotten an ICP we concluded the light intensity change seemed to be the issue by process of elimination).

A few months later now and I'm starting to look more towards sps / clams that will require higher light, but my PAR is relatively low (about 200 at the higher point in my scape, about 120-130 on the substrate. I run the hydras at about 85% with an almost all blue spectrum, but as I understand they can still give out more intensity.

I want to try and increase my PAR to be able to sustainably keep a tridacna clam and ideally some acros down the line, but am obviously incredibly anxious to be risking anything especially as I've gotten some higher end LPS since the original attempt. Any ideas how to do this "safely?" Thanks!

 

[blaxsun]

A lot of my PAR levels are in the 50-75 range on the substrate, rising to between 75-125 midway up my rockscape and capping out between 150-200 PAR near the top. I probably have a half dozen SPS in that 150-200 PAR range that are all doing well, but the vast majority of my corals are soft and LPS (volume by soft, different types by LPS).

As much as I'd also like a clam, I'm not necessarily convinced that I have enough PAR for it - despite the fact that everything else is doing awesome. So I've opted for the lesser of two evils at the moment, which is foregoing the nice clams my LFS has and ramping up my lights in lieu of keeping the other 100 or so soft, LPS and SPS corals and two dozen anemones happy with the current lighting configuration.

 

[Porpoise Hork]

Adjust the lights to get the PAR you need for the clams etc. and then use the acclimation mode to adjust it from the current setting to the new one over a span of 4-6 weeks. If you have low PAR corals higher up, they will need to be moved to lower PAR areas as the lights slowly increase in intensity.

You can also keep the overall PAR in the 200's on the upper levels and just increase the photo period by 15 minutes/week to add an hour or two as well. Many SPS will acclimate to lower PAR as long as they are exposed to a longer photo periods.

 

[cdw79]

My current schedule is just a 1 hour ramp up time either end of 8 hours of full photoperiod. I've heard about the acclimation function but not sure I fully understand it.

I currently have two leather colonies (a big toadstool and a green sinularia colony) on either end of the tank, and because they're pretty large they tend to get some higher PAR levels too. Is there a point at which I should be worried about them getting too much or is that unlikely?

 

[Wasabiroot]

I would go slower than 5% per week. More conservatively, give it a few months to raise from 85 to whatever you're looking for. Maybe 2% /week tops

 

[cdw79]

Without having to borrow the local PAR meter each week, is there any way to get a sense of what a good stopping point would be without reaching a similar point I did last time around with the bleaching?

 

[Wasabiroot]

Without having to borrow the local PAR meter each week, is there any way to get a sense of what a good stopping point would be without reaching a similar point I did last time around with the bleaching?

Honestly, clams love light, but some of the easier varieties (i.e. derasa) will do just fine at 150-200.
If your lights are at approximately 200 par at 85% intensity, then they should presumably be approximately 15% more par at the surface at 100% intensity.

 

[cdw79]

Honestly, clams love light, but some of the easier varieties (i.e. derasa) will do just fine at 150-200.
If your lights are at approximately 200 par at 85% intensity, then they should presumably be approximately 15% more par at the surface at 100% intensity.

Ah ok, I wasn't sure if the math was linear like that!

For that acclimation setting though, should I trust it to increase the intensity slowly enough, or would doing small increases manually be preferable? I only just realized it seems to be an option

 

[EricR]

Ah ok, I wasn't sure if the math was linear like that!

For that acclimation setting though, should I trust it to increase the intensity slowly enough, or would doing small increases manually be preferable? I only just realized it seems to be an option

Maybe this is a silly question but, for the Hydra LEDs, can't you just use the myAI app "acclimation" setting to slowly adjust it for you?

Meaning, if you're at 85% now and want to get to 100% in one month, just set for 100% and turn on "acclimation" starting at 85% with time period of 1 month.

 

[cdw79]

Ah gotcha, I'm not around my tank until this evening so I haven't been able to mess with it myself yet. Is 1 month ok or should I look to extend that? I'm more than happy to be as patient as needed, don't want to go through any more bleaching

 

[cdw79]

Just called the AI folks to confirm I understood the acclimation process, and I'm thinking about this as my plan going forward:

Increase the intensity from 85% to 100% across the blue and purple spectra
Increase my white from 10% to 15% or so
Choose a 60 day period so that each week has roughly a 1.75% increase
Reevaluate PAR after the 60 day period and see about going above 100%, which seems to be an option though I don't quite understand why

Does that seem conservative enough?

 

[Wasabiroot]

Ah ok, I wasn't sure if the math was linear like that!

For that acclimation setting though, should I trust it to increase the intensity slowly enough, or would doing small increases manually be preferable? I only just realized it seems to be an option

It likely isn't, and a par meter is probably the best course if you want the most accurate data.

 

[Wasabiroot]

Also: tread carefully here. You mentioned your sps are doing well...you might not need to change anything. Would hate for them to get fried.

 

[cdw79]

It likely isn't, and a par meter is probably the best course if you want the most accurate data.

Would you say that there is an upper limit I should be looking to stop at in particular? Vague question I know but I haven't really been able to find much info on that. Otherwise I figured I'd just follow my plan from above unless it seems questionable.

And only have some digis as far as sps goes- LPS is doing well but I haven't dabbled in acros yet bc the tank is still only about 6 months old. But it's the goal going forward for sure

 

[Wasabiroot]

I think your plan is sound, personally. Check and adjust as appropriate

 

[Porpoise Hork]

Without having to borrow the local PAR meter each week, is there any way to get a sense of what a good stopping point would be without reaching a similar point I did last time around with the bleaching?

You can rent a PAR meter form BRS if there's not one available from a local reefing club.

 

[cdw79]

We do have one, just costs about $30 and I just had it two weeks ago lol. Thinking the increase shouldn't be coral-frying levels if I'm only increasing it by 15% and I'm only between 100 and 200 PAR or so currently depending on where in the scape. So thinking I try and hit that 100% with a spectrum I like, test, and ovulate whether it's worth going higher?

 

[cdw79]

Updating an ld thread here, but ultimately got up to 105% across the board and still not quite what I was hoping for. I used our local PAR meter to see what I could max out my Hydra's at, and the results were more in my ballpark (though not the 250+ sandbed PAR for a Maxima, so when I do get it it'll have to be put further up the rockwork).

What I'm wondering now, though, is about how quickly or slowly to bump up the intensity. I have to go from 105% to about 145% this time, and it would take ~20 weeks if I did it the way I had done before, but that feels a little overkill. Would I be able to get away with, say 1% increase per day? I'm all abut being patient in the hobby but 5 months to adjust lights makes me feel like I'm being a little too neurotic for my own good!