How many Prime HDs for 90g?

Chrysantha · Oct 22, 2018

I'm looking at doing either the SCA 66 or 90, which have respectively dimensions of 32x24x20 and 36x24x24.

I'm not looking at many SPS, maybe a monti or two here or there, but I love the flow of LPS, so it will probably have just mainly euphylia and blastos, that kind of thing. What would you recommend in terms of the AI Primes? Would 2 over this length with the stocking be ok? I looked at the specs on the website, but I have to admit, I don't really fully understand my par, still trying to learn more.

Hitman · Oct 22, 2018

2 at minimum 3 would be better to prevent shadows.

tdileo · Oct 22, 2018

I would do a minimum of 3 on the 90 for good coverage and a mixed reef with minimal/no SPS. At that point though, I think you’d be better off just getting a pair of Hydra 26. $700 vs $675 for 3 Primes, or more money for a fourth. The problem with the Prime is it isn’t meant for 24” tall tanks. You’re going to have very little PAR at the bottom of your tank.

Fritzhamer · Oct 22, 2018

I’d probably go with three 26HDs instead. I think the issue you will have is the 24” depth. The intensity of the light drops off the further away from right under it you are. With three 26HDs (or non-HDs) you could light the tank well all over. The 26 non-hd can usually be found on here for around $175 each.

Michael Llabona · Oct 22, 2018

I would do 2 26HDs and potentially add a 3rd down the road if you pursue more sps. I think the problem you might run into is coverage front to back at the 20 and 24 inch depth. Also you might want to to consider a hybrid fixture. 2 ai primes and 4 t5 will out perform all of these. You won't have much shadowing but still have your shimmer. It's a win-win. Just my opinion.

Hitman · Oct 22, 2018

Michael Llabona said:
I would do 2 26HDs and potentially add a 3rd down the road if you pursue more sps. I think the problem you might run into is coverage front to back at the 20 and 24 inch depth. Also you might want to to consider a hybrid fixture. 2 ai primes and 4 t5 will out perform all of these. You won't have much shadowing but still have your shimmer. It's a win-win. Just my opinion.

^^^ This