Sump Question for the Experts

[MikeYQM]

My in stand sump is about 26 gallons right now with a partial refugium (DSB, chaeto & Mangroves) but I'd like to add extra rock & water volume. I don't have room for the rock in the sump so I'm thinking of doing a closed loop reservoir with a 36 gallon garbage can behind the wall.

Space on the back room is limited as I already have 2x 32 Gal garbage cans (RODI & Salt mix for auto water change), a 20 Gal can for kalk/ATO and 3x 5 Gal buckets for dosing. This is why I'm going for a can instead of an old tank. Also there's less flood risk.

I'm going to install two bulkheads in the can, one inlet from the sump plumbed to a tee at the bottom of the can to create an upward flow. The other bulkhead, slightly higher will be an overflow back to the sump. The can will have a lid and there will be plumbing for auto water change & dosing to help clean up my mess of plumbing under the tank now.

Are there any issues with placing live rock in the can to help with biological filtration? One concern I've heard is detritus buildup, but I'm hoping to fix that by putting my dirty water pump from Auto water change at the bottom to suck most out daily. Otherwise, I don't know if I can house hermits or Nas snails in there or if there are any other concerns about this setup.

Thanks in advance.

 

[THS]

The only problem I could imagine is that is wouldn't be a true "closed loop" since the can is not air tight/water tight. The water level in the can would vary, depending if the pump was before of after the can in the loop.

Maybe just use an overflow box to get water into the can, then a pump for return...like a regular fuge.

 

[JSeymour]

You should only need one bulkhead, the output. The can should be pump or gravity fed(from the display's overflow).

Gravity feeding from the sump will only allow the water in the can to reach the same height as the sump.

 

[MikeYQM]

If I pump water into the can from the sump, then let it drain from a higher bulkhead back to the sump, that would maintain a constant water height no? Wouldn't the water stay at the higher bulkhead level?

The can will be taller than the sump so I have no choice but to overflow back to the sump.

 

[THS]

Mike, I see what you mean now, yeah if the outflow of the can is higher than the water level in the sump, it will overflow back into the sump.

 

[JSeymour]

That would work, but only with a powerful pump(200+ lb. of back pressure with three feet of head). Any power outages would also be disasterous, as 25 gallons of water would come rushing back into the sump. A check valve would prevent this for a while, but eventually it would 'encrust' open and fail.

It would be much better to design the system to be 100% gravity fed and drained like my pic above. The wider central piping is to prevent air bubbles from becoming trapped below the live rock, killing off sessile organisms.

 

[Ron Reefman]

That would work, but only with a powerful pump(200+ lb. of back pressure with three feet of head). Any power outages would also be disasterous, as 25 gallons of water would come rushing back into the sump. A check valve would prevent this for a while, but eventually it would 'encrust' open and fail.

JSeymour, not if there is an anti siphon hole in the pipe from the sump pump to the garbage can tank. And where the heck are you coming up with 200+ pounds of 'back' pressure? Three feet of head in a pvc pipe isn't much at all.

OP, Mike, you need to draw up what you are planing so we can 'see' the design. I think your systems is unclear to some of us (me included).

 

[MikeYQM]

I'm not to worried about the plumbing; I'm confident in my design. My question is about the benefits/drawback of adding 60+lbs of rock and possibly a 6" DSB would have.

 

[JSeymour]

JSeymour, not if there is an anti siphon hole in the pipe from the sump pump to the garbage can tank. And where the heck are you coming up with 200+ pounds of 'back' pressure? Three feet of head in a pvc pipe isn't much at all.

OP, Mike, you need to draw up what you are planing so we can 'see' the design. I think your systems is unclear to some of us (me included).

That wouldn't work based on the design he wants(two bulkheads, input low and output high). An anti-siphon hole would do nothing in this circumstance. If the OP placed the input higher than the output, then yes an anti-siphon hole would work, but that's not what he is talking about.

I came up with 200+ lb of "back pressure" based off his concept of having the water pumped in from a bulkhead near the bottom. When 'full', the 25+gallons(200+ lb) of water in the can will naturally want to flow out the bulkhead in the bottom due to gravity and this not being a closed loop, i.e. 200+ lb of back pressure. The three feet of head is the trash can itself, not pvc.

I'm not to worried about the plumbing; I'm confident in my design. My question is about the benefits/drawback of adding 60+lbs of rock and possibly a 6" DSB would have.

I would highly recommend you rethink your plumbing design, but to answer your question, you would definitely see benefits from having more liverock, more water, and a DSB. The more, the merrier.

 

[MikeYQM]

There must be a disconnect in what I'm describing & what you're picturing.

Place a sump on the ground with a taller reservoir beside it. Pump water up into the reservoir through a bulkhead near the top with a anti siphon hole. Just above the inlet on the reservoir, the water will overflow through a bulkhead back to the sump.

Perhaps the confusion comes from my description of piping the reservoir inlet from the bulkhead (at the top) to the bottom of the can to create some updraft movement. Almost like a large unpressurized media reactor.

 

[JSeymour]

There must be a disconnect in what I'm describing & what you're picturing.

Place a sump on the ground with a taller reservoir beside it. Pump water up into the reservoir through a bulkhead near the top with a anti siphon hole. Just above the inlet on the reservoir, the water will overflow through a bulkhead back to the sump.

Perhaps the confusion comes from my description of piping the reservoir inlet from the bulkhead (at the top) to the bottom of the can to create some updraft movement. Almost like a large unpressurized media reactor.

lol, ok but that's not how you described it earlier.

I'm going to install two bulkheads in the can, one inlet from the sump plumbed to a tee at the bottom of the can to create an upward flow. The other bulkhead, slightly higher will be an overflow back to the sump.

Just make sure the input piping is higher than the overflow piping. I would still push you towards the design I drew. It doesn't require a pump to run(less electricity, less heat, and fewer things in the sump) and only has one potential point of failure, the one bulkhead.

 

[Purple Rocks]

I think a DSB would be better served in a container wich allows for more surface area.
IMO