New build- closed loop system

[Finnish reefer]

Hi all
I am planning to build a new reef tank in the near future so I’m here to get your opinions and tips for it.
First of all this won’t be my first reef tank, I have been in the hobby for 6 years now, but I would like to try something different.
In the past I have used wavemakers, but this build would be a peninsula, and overall I dislike the look of wavemakers
For this build I would like to use wavemakers only to complement a closed loop system. ( I know the risks of closed loops, I am here mostly to get your opinions on the flow)
The idea would be to build a SPS-dominated mixed reef
On the picture attach bellow the is a drawing of my vision so far.
The red,blue and purple circles with the arrows are closed loops on the bottom of the aquarium, the pink semi-circle woul be a closed loop on the surface of the aquarium and would be linked to a sea-swirle.
The green circle would be the return line that would also be linked to a sea-swirle.
The three black rectagles would be the aquascape the rectagles would be the intake for each respective close loop.
The wall would be on the left side of the aquarium.
The idea would be to have good turbulent flow between the islands . The nozzles on the bottom closed loops would be aimed upward and the pumps would be cotrollable DC pumps so the point were the different flow hit each other would vary during the day. The nozzles would also have RFG:s. For the surface closed loop, I was thinking a Y connector and eductor nozzles so the flow has the velocity to get to the other end and the Y-fitting would provide the sea-swirl 180° covereage.
For the return pump I was thinking RFG-nozzles aimed downward (not dirrectly at the corals) and a three way split fitting so combined with the sea-swirl, they would cover the whole aquascape.
I am really looking forward for any insight that you may have

 

[bluemon]

If doing close loop, definitely do not skimp out on the return pump.

I’m not saying you should get an Abyzz, but…

Excited to follow along. Always was interested in a closed loop system

 

[WhatCouldGoWrong71]

I have 3 closed loops on my system. I wouldn’t do a reef tank without at least 1 going forward. I have a bunch I want to share after reading your post , but I am short on time. I’ll post again later tonight. But, the one thing I want to address is what popular YouTubers (I’ll leave names out) say about and why regarding closed loops. Many of these tanks running are older and very mature. I spoke to 3 of them, probably the same 3 you are thinking about right now. None used Hayward bulk heads with EPDM gaskets. I personally had a call with an engineer who specialized on saltwater containment systems. EPDM is ideal and very very long lasting. Most if not all of the bulkheads in those popular YouTuber tanks are the $10 bulkheads not the $60 premium ones. Now, understand, the tolerances to cut a hole for a Hayward are almost non existent, meaning, you either nail it by special ordering the size. And, I love the reverse thread. But, I would not get NPT on the intake side again, only on returns. Also, don’t use grease on the gaskets like you do on most other gaskets, the pressure will push the gasket out and instaleak. I worked extensively with Antonio at VCA, great man. I think I have 18 RFGs in my tank. You’re going to want to learn and understand flow (fluid dynamics) Chat GPT can be your friend. A lot can cut down on flow quickly.

Moral of the story. Everyone I talked to complains about loops, and they all asked me not to do one, true story. But, when I brought up this specific bulkhead, I’m guessing it wasn’t a thing when these gorgeous mature tanks were put together.