Plumbing 3 tanks (reef, FOWLR and display refugium) to one sump

[waitwut]

I currently have a Red Sea Max e 260 + sump add-on + DIY refugium set up as a mixed reef tank and it's running successfully so far (around 9 months old now). Yes, before I get any further, I'm fairly new - I'm planning ahead because any equipment/tanks/cabinets/etc I buy now I want to still be using in a few years time. This would be a long term project.

I have a Fluval Flex 123 that I'm currently using as a QT but eventually I'd like to turn it into a FOWLR predator tank - likely with a valentini puffer as the centerpiece. From what I've read a valentini can get by in a 30 gal tank but water stability/quality is going to be a concern so I'm thinking about ways to improve stability and export nutrients.

I really like the idea of a display refugium to export nutrients and to showcase things I can't put in a mixed reef (or in with a puffer as they'll get eaten) - maybe a mangrove, various macroalgae, crabs, anenomes, etc. I could plumb the FOWLR + refugium together onto one sump but as I started considering the cost I realised I could instead plumb all three tanks together into one large sump and save a fortune on equipment and loads of time on maintenance. I also already have a GHL profilux running ATO + AWC among many other things - I'd like to get the most out of this expensive bit of gear and so the idea of one big system is especially appealing.

The downsides that come to mind:
- risk of disease
- tank crash / equipment failure hitting multiple tanks at once
- predator tank waste overwhelming the reef tank
- waste of reef salt/additives on a FOWLR tank (though I assume the FOWLR tank won't really use up the additives)
- unable to treat fish diseases because of the inverts in the system (but this is a risk with the display refugium anyway and I will of course have a QT/hospital tank as well)
- need to size sump to handle water from so many tanks/pipes

Upsides:
- no need to buy duplicate equipment
- increased water volume and stability for all 3 DTs
- reduced maintenance (only need to test 1 tank, AWC covers all tanks at once, etc - this is the big one for me)
- reduced power use - 1x return, 1x skimmer, etc, which is also big as I'm in Germany and power is painfully expensive

Plan would be to put the Fluval 123 and the display refugium onto one big custom cabinet alongside the Max 260 and build a large DIY sump underneath, likely with inlets on either side and a single return pump chamber in the center. Plumbing the 260 into the new sump will be a little tricky but I think achievable - and then I can remove the current sump and use the space for other gear or a remote DSB or something. I'm hoping that I can keep the need for WC to a minimum with a large refugium so there won't be too much reef salt wasted on the FOWLR.

Interested in feedback on the plan - am I underestimating the waste output from a predator tank? Is it realistic for one large display refugium to export that many nutrients (I'm thinking at least 30-40 gallons)?

Most importantly - does anyone have experience with a setup like this or any advice? Would love to see photos!

 

[tbrown]

One thing to consider when sizing everything is that the single sump has to be large enough and have enough headspace to handle the flow from all 3 tanks in case of a power outage or any maintenance you do that requires the return pump to be shut off.

As you mentioned above, disease can be a problem if you have multiple tanks plumbed together. Ich/Velvet/etc can potentially wipe out all 3 tanks. Also, any hitchhikers can travel from tank to tank.

This is something I have considered in the past as well. I think it's a cool idea with a lot of pros going for it. Considering the cons and making sure you're prepared for them is key.

Good luck!

 

[MoshJosh]

I have a 5 gallon and a 29 gallon plumbed into the same sump. . . made out of a bucket. Both tanks have their own separate overflows but go through the same filter sock. Both tanks have their own return pumps as well.

 

[00W]

I run 2 tanks off of one sump.
I've run 2 return pumps but currently only running one. Each tank has it's own overflow. I've also run 2 skimmers as well.
It definitely cuts down on costs.
It looks like you have examined all options really well-nice job.
Good luck. Any questions, ask away.
Joel

 

[waitwut]

I do have some questions! Was there a reason you switched from 2 pumps to 1? Did you have difficulty getting the flow rates right with 2 pumps? Were you running the two pumps for redundancy or were they feeding separate tanks? Did you have a single return pump chamber?

If I'm plumbing everything into one sump I don't want any single point of failure to take out all three tanks, so I like the idea of redundant pumps i.e. running two pumps with each feeding all three tanks, but this has a few challenges - balancing flow would be tricky and if one pump fails the water is going to siphon back through it while the other runs, though I'm not sure this really matters particularly much as it just becomes an additional overflow.

I've considered building the sump the other way around - so inflow in the center and a return chamber on either side with 2 separate pumps, but I think this would make setting up ATO difficult. Inflow on either side allows me to filter differently as well - I am considering putting filter socks on only one tank's overflow, probably the reef tank, so that waste food from the FOWLR can circulate through the system and be picked up by filter feeders in the refugium and the reef tank.

 

[DJF]

I recommend having 1 return chamber and water flowing 1 direction. I have 1 sump feeding 3 70g tanks (while I prep a 400g tank). Currently 1 pump feeding all 3 but would consider having 3 individual smaller pumps feeding individually. I do it to keep my sps separate from other corals and each is tailored to flow needs. Only issue I could see with a fowlr is if feeding caused a phosphate or nitrate spike that the coral couldn’t handle- def doable.

 

[waitwut]

I'm hoping the refugium will offset any nutrient spikes but I'll definitely need to monitor that closely, particularly when first plumbing them together. I intend to set up the refugium soon with some live rock from the reef tank and let it become an established ecosystem in and of itself before I plumb them all together - stocking the FOWLR will be the final step once the full system is capable of handling the additional bioload.

Anyone have experience specifically with predator tanks + refugiums? I like the idea of designing it such that the waste from the FOWLR ends up circulating through the rest of the system and feeding the refugium inverts and filter feeders, but I'm aware that a predator being fed a few times a week is going to result in major nutrient spikes. Would I be better off focusing on mechanical filtration here (socks or a filter roller) that will take the bulk of that waste out directly?

 

[00W]

I went to one larger return and put in valves to each tank just in case.
I didn't want to but went with a dc pump saved my ac pumps for spares.
The valves became unnecessary because I can just adjust the flow. The new return is silent and produces no heat so I'm happy.
Never had a return fail so can't help there.
Always check sump water availability if all pumps are off!
Install check valves. They work.
They can fail too so just make sure your tank returns aren't too low in each tank.
I drill holes in each return right at water level.
Helps. That's a great failsafe.
One return chamber is best at the end of the line.
Keep asking those questions.

 

[00W]

Where you return the water from either tank really doesn't matter. It's best returned in the first chamber. I like to filter the water before the skimmer. Seems like the best option.
But I've returned one into a fuge, into a rock filter and into a separate sock past the skimmer as well.
I have very slow flow through my sump.
I've also had a pump in my return chamber that just put water back in front of the skimmer too.
Just remember. Zero nutrients is no Bueno. You need something.
Fowlrs are great for that.
Oh yeah.
Have fun.

 

[KrisReef]

The predator tank should flow into the reef so the corals can suck up the ammonia before the refugium or live rock get a shot. It will be a challenge to keep up with imports and exports.

 

[waitwut]

I was considering having the predator tank flow into the refugium to process the waste but it had never occurred to me to have the FOWLR flow first into the reef tank - any particular reason? I would imagine that the concentration of nutrients is going to be pretty consistent throughout the system with a decent amount of flow so I was only thinking about solid waste and I assumed that would be best processed in the refugium.

Unfortunately getting the FOWLR to flow into the reef tank would be very difficult as the water level is going to be substantially higher (20cm+) in the reef tank so I'd need to put the FOWLR up on blocks or something on top of the stand which would look pretty weird.

Plumbing the FOWLR to flow into the refugium would be a challenge if I have a single large cabinet as the two tanks will be on the same level - the refugium tank will definitely be shorter than the FOWLR and have a lower water level so it would be possible. I also can't drill the Fluval tank as it's tempered glass so it will need to be a siphon overflow (or two). Perhaps I can set up a double siphon overflow and have one drain pipe taller than the other to act as an emergency overflow with the shorter flowing into the refugium?

Isn't flow rate also a concern with a setup like this? If I understand correctly, if the outlet into the refugium is underwater (which I think is necessary to avoid noise) the flow rate would depend on the height difference between the water level in the two tanks and the width of the pipe itself. With such a small height difference would I be able to get sufficient flow to turn over the water in the FOWLR tank?

If anyone has experience plumbing tanks together in series like this with a common sump I'd love to hear how it went and see some photos!

 

[00W]

I'm starting to get really confused .
Here's a picture of my ugly sump.
Tank has been going 7-8 years on left, 4-5 years on right.
I feed the left tank twice a day heavy.
110 gallons total volume running at 15.1 nitrate tested today.
Water change every Monday.

 

[waitwut]

Describing it is getting a little confusing - here's the layout and the two options I've been considering:

 

[00W]

Wow nice drawing. Wish I could do that.
Either way works.
Second drawing you should use two returns. One just for the red sea.
The only thing I can tell you that I've never figured out is that both these tanks use the same water and each one is totally different.
Go figure.
Remember also the tank furthest away from the pump usually but not always will flow slower.

 

[waitwut]

I just use draw.io

Distance is one of my concerns with sizing the pump and also one of the reasons I was considering having the return pump chamber in the center. The longer my return lines the more power my return pump is going to use (and the bigger it has to be).



This discussion has made me realise that if I'm going with one of the options above (with the sump flowing in one direction) the return chamber should be on the right hand side of the sump, not the left, to make the lines shorter.

 

[00W]

Yes all of that is correct.
You seem to have a great grasp on this project.
I ran my return in the middle for years with a skimmer on either side so, yes that's an option.
Power bill being a concern, go DC pump and it'll save.
Reef octopus varios are great pumps with high longevity.