What To Consider When Buying A Large Tank

[BPro32]

My thoughts on the designs:

First I'd like to see the heights, because I think that is very relevant when it comes to how much water volume is in each of the sections and accounting for how much safety buffer you'll have if your return pump loses power.

Earlier you said you don't want a fuge. I think having the option for a fuge is great, but at the same time having a bigger return pump section also has advantages. For example, if you ditched the fuge and had a return pump section that were 24" (wide) x 15" long x 12" high (estimated water height), that is about ~19 gallons. Depending on how low your pumps can run, this means you could remove somewhere between 10-15 gallons of water without having to turn off any pumps, the only thing that would change would be the water level in the return pump section. Pump out 10 gallons, pump in 10 gallons. You just did a ~5% water change. To do a 10% water change, just do it twice. The smaller the return pump section is, the less water you can pump out before your return pump runs dry. This also is fine, but I think it makes water changes a little more annoying. Just something to think about when considering the fuge section.

I'd also check out the size of your "inlet" area. If you are going to run a beananimal style overflow, which I highly recommend, that means you are going to have 3 pipes coming in (or at minimum 2 if you have the emergency drain going elsewhere). In that 2nd design in particular the inlet area looks very cramped to me. The first one might be OK if you have a glass sump that has no bracing, but if there is any bracing then it is going to be really hard to access. Stuff will fall down there from time to time so you want to make sure you can reach to the bottom of the section, when it is full of pipes, if necessary.

I agree with your point on the second design. My preference is the first, but I've heard from others that having 4x4" socks is going to be annoying vs 2x7".

I was thinking 8-10" water level in the skimmer section and bump down .5-1" each section thereafter. With an 18" total height I think that gives me plenty of room for back siphon in a power outage.

The fuge section is really more for extra live rock and frags. When I cut softies I throw them in the sump in a low flow area to attach to rubble, then I can sell them or trade them in. For water changes I have a really long hose and U-shaped pvc that drains to a set amount. As far as I can tell, that's roughly the same amount of work vs attaching a hose to the manifold and pumping out from the return pump but I'd love to hear your thoughts.

 

[BPro32]

Based on personal experience, I like the 7" socks way better than the 4". Much easier IMO to turn inside out for cleaning. I throw mine in the washing machine when my wife isn't home

Sent from my SM-G950U using Tapatalk

That's a really good point. Back to the drawing board to make 7" socks fit but also have an accessible inlet area. I really want to make the fuge/frag area work in the sump instead of having to connect a small frag tank (because I don't have the room).

 

[sfsuphysics]

I might be weird, but I like to put the skimmer compartment after the fuge compartment, here's why
1: Water height, fuge will typically be a nice high area, where as skimmer all you need is 7-9 inches (adjustable baffle piece makes this a breeze)
2: Sure you can always put your skimmer on a stand but you might find with larger skimmers you really don't have as much room under the tank as you might think.
3: Extra empty volume, with a smaller skimmer area you will have more empty space in case of power outage or what not to hold extra water from the tank. Sure the skimmer might overflow due to the rising water height (unless you do some next level thinking and install a float switch that doesn't let the skimmer operate if the water level is too high) but a skimmer that overflows is much more desirable than having the sump overflowing onto the floor.
Sure you run the risk of your precious "fuge critters" (food) not making it to the main tank but it's a risk I'm willing to take.

I agree the 7" socks are much more friendly for turning inside out, that said I use mostly the mesh socks that captures larger stuff (food, poop, algae that you scrub off etc) and those are super easy to turn inside out and you can rinse those off super easy and almost wring them dry. And if I feel like I need an extra polish I do have the felt socks.. but don't use those because yeah they are a pain to turn inside out, but I'd rather have the extra 3" in my sump than have than have ease of cleaning socks

 

[JVU]

I don't think skimmer after fuge is weird or unusual. That's how my stock Red Sea Reefer sump is set up for example.

If you are going to use filter socks (a lot of people prefer not to) then I'd use the thin plastic ones like the ones that come with the Red Sea Reefers, they are a lot easier to clean.

 

[sfdan]

I agree with your point on the second design. My preference is the first, but I've heard from others that having 4x4" socks is going to be annoying vs 2x7".

I was thinking 8-10" water level in the skimmer section and bump down .5-1" each section thereafter. With an 18" total height I think that gives me plenty of room for back siphon in a power outage.

The fuge section is really more for extra live rock and frags. When I cut softies I throw them in the sump in a low flow area to attach to rubble, then I can sell them or trade them in. For water changes I have a really long hose and U-shaped pvc that drains to a set amount. As far as I can tell, that's roughly the same amount of work vs attaching a hose to the manifold and pumping out from the return pump but I'd love to hear your thoughts.

I'm not sure I understand the mechanism you are describing for water changes. If you keep the return pump on, whenever you remove water from anywhere in the tank, only the level of the return pump section will drop.

And for the skimmer location, the only downside I can think of to having the skimmer later in your sump is there is less time for any micro-bubbles that make it out of your skimmer to dissipate before potentially get pumped back into the main tank.

 

[sfsuphysics]

Another big piece of advice make sure your skimmer, the body and cup can be put into your sump when it is in place. I almost screwed up big time with that but luckily I clamped a piece of wood to my stand at the original height for my sump (18") and found out that while my skimmer cup could be removed the body could not be removed, which is always good to have for periodic cleaning/maintenance. Luckily I caught the flaw before I sent the size requirements to the builder.

 

[BPro32]

I'm not sure I understand the mechanism you are describing for water changes. If you keep the return pump on, whenever you remove water from anywhere in the tank, only the level of the return pump section will drop.

And for the skimmer location, the only downside I can think of to having the skimmer later in your sump is there is less time for any micro-bubbles that make it out of your skimmer to dissipate before potentially get pumped back into the main tank.

Basically it's a siphon that automatically stops after a set number of gallons. I turn the pump off, start the siphon, then I can prep the new incoming water while it's draining - i.e. connect the hose and get ready to turn on a pump once the siphon is done.

 

[BPro32]

Another big piece of advice make sure your skimmer, the body and cup can be put into your sump when it is in place. I almost screwed up big time with that but luckily I clamped a piece of wood to my stand at the original height for my sump (18") and found out that while my skimmer cup could be removed the body could not be removed, which is always good to have for periodic cleaning/maintenance. Luckily I caught the flaw before I sent the size requirements to the builder.

I've done this before...

 

[BPro32]

I might be weird, but I like to put the skimmer compartment after the fuge compartment, here's why
1: Water height, fuge will typically be a nice high area, where as skimmer all you need is 7-9 inches (adjustable baffle piece makes this a breeze)
2: Sure you can always put your skimmer on a stand but you might find with larger skimmers you really don't have as much room under the tank as you might think.
3: Extra empty volume, with a smaller skimmer area you will have more empty space in case of power outage or what not to hold extra water from the tank. Sure the skimmer might overflow due to the rising water height (unless you do some next level thinking and install a float switch that doesn't let the skimmer operate if the water level is too high) but a skimmer that overflows is much more desirable than having the sump overflowing onto the floor.
Sure you run the risk of your precious "fuge critters" (food) not making it to the main tank but it's a risk I'm willing to take.

I agree the 7" socks are much more friendly for turning inside out, that said I use mostly the mesh socks that captures larger stuff (food, poop, algae that you scrub off etc) and those are super easy to turn inside out and you can rinse those off super easy and almost wring them dry. And if I feel like I need an extra polish I do have the felt socks.. but don't use those because yeah they are a pain to turn inside out, but I'd rather have the extra 3" in my sump than have than have ease of cleaning socks

The main reason I'm designing it skimmer first is to save room in the sump for back siphon. Otherwise I agree that fuge first is great so you can have a bigger fuge w/o the need of raising the skimmer.

I did just do a back siphon test on my current tank. When the return switches off, the water level in the main tank drops about 3/4". Even if I double that on the new tank, the back siphon will be ~16.5g which would be well within the limits of what even a small-ish sump could handle. I'm more confident that I can go with the bashsea sump, though I would choose the 48x18 version, and fit everything I want in there.