2 + 2 = 4 ?

[Idech]

I had 2 AI Prime 16 HD on my 75 gallons, 48 inch wide and 21 deep tank. I have LPS and softies. I had the intensity set at 90% and everyone was doing fine.

Then I added 2 more AI Prime 16 HD, to eventually get into SPS also. I set the lights as 2 separate duos and have them both at 55% intensity right now.

Here is my question : without a par meter, what is the best guestimate for intensity so that it is close to the 90% I had before ?

Thanks !

 

[Utubereefer]

Just because you have more spread doesn’t mean you have the same penetration of light. Without a meter everyone is guessing. Read your corals for signs of happiness or stress

 

[Idech]

Just because you have more spread doesn’t mean you have the same penetration of light. Without a meter everyone is guessing. Read your corals for signs of happiness or stress

Yeah, I know. I’m hoping for an educated guess. I’ll get a par meter eventually.

All corals are doing fine except my frogspawn that is staying small. But it’s always been very pouty so I don’t know if it’s the light or just it’s usual state.

 

[jda]

Froggies can take a very large amount of light, but they don't need it. I used to keep them in well over 500-700 PAR from my MH and they grew like crazy, but they also did fine with much, much, much less.

Do you live anywhere near a larger city with a reef club? Many of them have PAR meters to borrow or rent. I know that this is not always possible, but worth looking into.

Generally, if your stuff is doing well, then you are OK... especially if you have the personality to just not tinker or go really slow with things (not all do). This is a much better gauge than a PAR meter, anyway. Keeping an eye on this, including looking for the smallest details like new growth, flesh extension over the skeleton, etc. is really helpful. I only purchased a PAR meter to test out LEDs when I was offered a bunch of units to switch... and also to just post/help about PAR and meters on the internet. My corals look great and I would not know or care how much PAR that they have unless I had the instrument already.

 

[Idech]

Do you live anywhere near a larger city with a reef club? Many of them have PAR meters to borrow or rent. I know that this is not always possible, but worth looking into.

I do but I am not aware of any saltwater reef club. I have a LFS that rents them so will do that eventually.

Generally, if your stuff is doing well, then you are OK... especially if you have the personality to just not tinker or go really slow with things (not all do). This is a much better gauge than a PAR meter, anyway. Keeping an eye on this, including looking for the smallest details like new growth, flesh extension over the skeleton, etc. is really helpful.

I am very patient and can go as slow as needed. I’ve been keeping fish tanks for more than 40 years so I know the virtue of slow, lol ! I’m new to saltwater though.

I’ll definitely keep an eye on things and see how it goes. I’m giving the frog spawn one more week and then maybe I’ll move it a bit.