DIY Sump/Refugium Questions - Help Needed

[jon770]

Well...I finally decided to build my refugium. I wanted to post my plans and get feedback on it. PLEASE tell me if anything I'm doing will not work or can be done better.I have a 75G display and the sump/fuge will be a standard 29G (20x12x18).
Water enters in RIGHT chamber from overflow. This section will include my Protein Skimmer (and my UV light, if/when necessary). There are 1-inch baffles to MIDDLE chamber, which is the return. A Mag-9.5 (or Mag-7, I haven't decided yet...any thoughts on that?) will return to display. The return will have a T joint which will allow some of the water to be sent to refugium in the LEFT chamber, which will be controlled by a ball valve. Water enters the fuge through an area filled with rubble rock, and filters into the main fuge area. I will have approximately 4 inches of sand here, along with all the proper algea and critters. I was also planning on taking my heater out of the display and placing in the fuge area of the sump...should that be ok? Also, I will put a PC light over the fuge area (probably an 18W aqualight, or something along those lines); will that be enough light? The water from the fuge then flows back into the MIDDLE chamber through teeth on the baffle and gets returned to the display tank (with a portion going back into the fuge).
Also, what type of silicone should I use to glue the baffles? Do I need special 'aquarium' silicone, or can I use the stuff from HD? Any type I should definitely NOT use?
Are all my baffle heights ok? I think I should have approximately 8 gallons of space left over in case of power outage, etc.
Anything I'm not thinking of that I should do? I don't want to have to make any modifications or re-build once it's made. This is my first attempt at ANYTHING like this, so I may be way off in my plans...
:help:

 

[jessecnc]

Jon, I see a few problems with your setup. First, concerning the refugium, you want to "T" off the line coming from the overflow to feed the fuge unskimmed, raw tank water. This provide nutrients to the fuge inhabitants, making it more effective.
Second, I do not believe you have left enough room for backwash. The available space left is 12"x12"x8" = 5Gal. If your overflow is even 1.5" below the water surface you will backwash 48"x18"x1.5" = 5.61Gal. This does not count the water in the return pipes either.
Also, the heater is probably better off in the return pump chamber. It should be more effective there, and putting it in the fuge may make the water too hot for pods, etc.
As for your pump choice, this depends on the flow rate of your overflow and your return pipe(s) selction.

 

[jon770]

OK.
The reason why I "T"-ed the return line instead of the overflow is because I wanted to reduce the flow in the refugium. I though that the flow in the refugium should be much less than what's running through the entire sump. If I "T" the overflow, then my refugium will get half the flow from my display (so assuming it's approximately 600gph...then the fuge will get 300 gph). Isn't that a bit much?
I didn't originally see it as a problem to have the water entering the fuge after going through the protein skimmer section (especially because not ALL the water in that section will actually go into the skimmer...some will pass straight through the baffles). In fact, most of the sumps/fuges I see are the following format:
SKIMMER --> REFUGIUM --> RETURN
Am I wrong? :notsure: Just curious if anyone has that setup (or the one I'm considering), and is regretting putting the skimmer before the fuge?
Also, how should I correct the backwash issue? What should I change to allow for more backwash space? Should I decrease the size of the fuge? Decrease the baffle heights?

 

[jessecnc]

Jon,
By installing a ball valve after the "T" to the fuge you can control the flow just the same. And you're right, the fuge should have low flow, although 300GPH is acceptable.
Concerning the fuge, I'm not saying it is wrong to put the fuge after the skimmer, just not as effective. You can keep the same layout you have above, just "T" the overflow instead of the return.
As for the backwash issue, first figure out how many inches the tank will drop to the overflow. Then multiply that by the length and width of the tank, and divide by 231. This will give you the backwash amount. Figure another 1/2 gal. or so for the water in the pipes. The best solution I see would be to reduce the size of the fuge. If you lower the dividers too much, the pump may suck air, and there will not be much room for evaporation.

 

[jon770]

Sorry...I should have described my surrent system a little more: My overflow is set up at the moment with the 'pool' type plastic hose, which drain into my sump. Is there a way to "T" those hoses and then add a ball-valve? I didn't think that was an option...
Can I switch the hoses to PVC with a bulkhead in my overflow box? Then using a "T" would be easier I guess.
If I kept the hoses, then what are my options?

 

[jon770]

Also,
If I want to decrease the volume in the fuge area, to allow for more backwash space, what's the best way to do that? I can make the length of the fuge section smaller, or I can make the baffle (going to the return area) shorter. Basically, what is a more desirable fuge: a TALL Fuge or a LONG Fuge?
Conversely, if I decide to lower the baffles (and keep my fuge at its current size), it seems that I would have more than enough room before I would have to worry about the pumps sucking air. In the current sketch, there is 9 inches of water in the skimmer section and the return section. The pumps' intake is only 2-3 inches...and if I need to I can even modify it with a PVC elbow to lower the intake even more...

 

[jessecnc]

Keep in mind that the return pump chamber will usually be a little lower that the other chamber because it is pumping from there. Also, as evaporation occurs, the return pump section will suffer the most. This does not mean it won't work, it just means you will have to be careful to watch evaporation.
As for the TALL vs. LONG fuge, I really don't know if one is better than the other. IMO I would go for a taller fuge. But that's just me.
And for the "T" options, I'm sure there is a way to add one to your current setup. I am, however, a fan of hard plumbing as long as you don't have to add too many fittings to make it work. This can dramatically lower the flow rate, although since the overflow is gravity fed, it won't make too much of a difference. Stay away from long horizontal stretches if you can.

 

[jon770]

Thanks Jesse, I really appreciate your input.
Just curious if anyone else has any other ideas? No disrespect to Jesse...I just know everyone has different experiences in this hobby and would love to hear from more people.

 

[jessecnc]

I agree completely! Get as many ideas as you can and form your own opinion. As anyone here will tell you, there are a million ways to do it, and there are just as many right as there are wrong. That's what makes this hobby so addicting!

 

[nytrillium]

Tall vs. long.
My understanding is that a fuge is just that ... a refugium. So you have to decide what your main goal is. TO grow macroalgae for nutrient export, or to grow pods? In the first case, surface area is more crutial since algae needs as much light as it can get. In the second case, overall volume is more important as well as live rock for reproduction/cultivation. So its pretty much up to you....
Im working on my sump/fuge/algae scrubber right now and i am doing a separage algae scrubber with dimensions 30"x12"x7" and my fuge will be half of a 20 long.

 

[jon770]

bump

 

[biggredd]

Have you created it yet? I am interested to see how your final product came out and if it is working successfully. I am startin my 125 tank and have a spare 29 the same size as yorus I am going to use in the meantime (the 55 gallon will come once I get more money - I'm already at like $700 and ticking with a long way to go). A pic would be great!

 

[jon770]

Not yet. I have all the materials and just waiting for the time to cut the acrylic and make the teeth for the baffle going from the fuge to the return. I'm probably going to just 'wing it' with the teeth and try using a dremel or something else I can find around the garage...
Ill let you know how it goes, when it goes.

 

[jon770]

So...I FINALLY finished my fuge after months of planning, and here are some pictures (before it was installed). Everything is now set up and running perfectly. I did the 'power-outage' test and have MORE than enough room for backwash. All-in-all, I am VERY please with how it came out. I even added racks to run carbon, etc....

BTW - There are absolutely NO bubbles from the fuge section to the return section (as seen above)...obviously, the freshwater from my hose is much less dense than saltwater and b/c of that created a bit of a waterfall effect. I got worried for a second, but it is perfect...