Sump design - issues from tank 2 > 3

[Deej1534]

Wanna get some experience from people who have built their own sumps. I have a DIY I have been using for about 4 years and recently upgraded from a 125 gallon to a Red Sea 900 xxl. I want to incorporate the Red Sea sump into my current one and add a frag tank into it for cut and holding new corals after quarantine. I am using 2” piping for the sump all around other then the Red Sea sump which came with around 2” pipe from manufacturer. I am going to have a glass company cut the second Red Sea sump which is sump 2 and add a 2” bulk head in the center of it. I included some sketched designs. Which are rough designs. The main thing I am trying to figure out is connecting sump #2 to sump #3. The issue is sump 3 is a tank I was given by my lfs and was pre cut with 1” holes. They were cut at the top of the tank and all my other cuts are at about half the height of the sump. In my head there are two solutions

1. Have the sump be below the sump stand so the water flows down to it and then is pumped back into the system using a small pump
2. Use a siphon and see if the water pressure is great enough to push the water up about 5”s.

I have no experience when it comes to have water travel up but I know gravity doesn’t like it lol I wanted to see if anyone else has had these issues and what there solution were.

I have considered using a T connection as well and have the water move from sump 2 to sump 4 and then also split to sump 3 and just control water flow to sump 3 with a valve. I have included pictures showing the design I have in my head. This will be in my basement just as an idea of where it is being built. Also I am not an engineer so drawings aren’t perfect. The cross hatching in the second photo is the stand I am building.

 

[strich]

I'm struggling a bit to understand the configuration you're working with so I cannot provide too much value. But I would suggest avoiding a gravity siphon just on the fact that it can and will stop randomly at some point.

 

[RocketEngineer]

I think I follow. My suggestion begins by placing the return pump in the middle. Have the skimmer section flow into the frag section, then to the return pump area. The refugium should be the tank with the upper drains and that flows downhill into the return from the other side. The result would look something like my old sump.

By having the return in the middle, you can use the full height of the refugium for growth. I fed my refugium off my main return pump for the life of that system and was regularly removing chaeto.

Just a thought.