Sump vs cannister....? Pros and Cons...

[Pomacanthus]

OK admittedly Im a saltwater guy but dont hold that against me...FWIW I despise cannisters for a multitude of reasons, Ive been a wet/dry and/or sump guy for the last 20 yrs and I never met a cannister I liked..should also admit that i design and build aquariums and aquarium systems for a living. Main bias is opening and/or cleaning a cannister is about as much fun as checking your kids head for wood ticks...Hey Im in MN..so heres the deal FIRST plant tank ever coming online so far I got the tank 60 x 18 x 26
Gonna light it up with 2 x 250W 6500K halides. Thats about all i know so far. Had this crazy idea to run the return lines flush left and right and venturi the C02 into the return lines coming out about 2" above the surface alternating left to right, i.e. blast left, then blast right. Secondary idea is a reactor, so my question has anyone ever done research on maximum C02 saturation techniques? I would think the reactor would win? BTW I read some posts on filling the overflow up to decrease airation (loss of gas) which is fine if you remember that the only failure point on a gravity drained tank is the overflow. My other option could be a closed loop system with 2 pumps to return water left and right (on timers to alternate) there by eliminating the sump entirely and still providing the left and right blast of C02..? Any feedback appreciated. BTW I dont see the gas as a big issue on sump issue, I understand minimizing loss, but I think i pay about $30 to fill a gigantic bottle thats as tall as I am
(6 ft) gotta believe that it would last at least a couple months..? Maybe Im wrong never been down this path. Seems like a small price to pay compared to a $600 protein skimmer for a reef tank...

TIA New guy Pomacanthus

[Pomacanthus]

Sump - Surface removal of proteins thru overflow, thereby increasing amount of light penetration into tank, protein buildup happens on water surface forming what i refer to as "the oil slick" (see Exxon). EZ water changes, I planned this out in advance so i have dedicated floor drains. Water changes so EZ my sister could do it, add digital timer to water holding reservoir with dedicated submersible pump at a total investment of around $50 and your done, you will probably have time to finish the kids treefort now with all the time and agony your saving yourself on water changes! Another advantage is EZ dosing of chemicals and/or fertilizers. The big CON is the wasting of C02 which is inevitable, but can be minimized with proper precautions - I hope Im right cause if I end up burning thru the gigantic cannister every 3 weeks Im gonna wish I could have learned to like cannisters

[nate_mcnasty]

wow second new guy from MN today i've talked to i to live in MN and doing a sump for my 55 i think a venturi would be better for this tank and i don't really think you need the 2 pump idea but i'm not sure on that and youll need to make your sump a low flow sump to prevent off gas

[SCMurphy]

I use sumps on my tanks as reservoirs to keep the evaporation from showing in the tank. The sump in this case is not a filter and with the way I constructed the 'overflows' there is minimal chance to degas CO2. Wet/drys are intended to do a biological filtration, are they not? That is what we use the plants for so a wet/dry actually competes against the plants.

[lauraleellbp]

I'm not so sure I'd consider a wet/dry in competition with plants, unless there's a denitration device installed somewhere; otherwise a wet/dry performs the same role as a canister filter. Ammonia and nitrItes are still being converted into nitrAtes which are then still taken up by the plants...

[SCMurphy]

Canisters are more for mechanical and chemical filtration. They are rarely set up to function as effective biological filtration units. They are advertised to be so, but unless you fill them with nothing but bioballs, ceramic noodles, or lava rock, etc., they quickly become too clogged up to be effective biological filters. If you do set them up like this, you lose out on the majority of their mechanical filtration ability.

[lauraleellbp]

You can easily customize either type of filter to serve any or all of those purposes, though. Filter socks, foam, media bags are all pretty common mechanical and chemical media for wet/dry filters. You can customize most canisters to function however you want them to. Wet/drys may take a little more forethought, but are just as customizable.

[Aqua Dave]

Sump pros: less equipment in tank, constant water level in tank, surface skimming, oxygenation of water, more water, customizable system

Sump cons: real-estate taken up in tank by overflows, higher CO2 usage, typically requires much more DIY work, usually noisier though that can be minimized


I think canisters work great for smaller tanks and for people not interested in DIY work. I have an Ehiem Pro II on my 45 gal and it is nice. Cleaning is not difficult as I just detach the canister and take it over to the sink for cleaning. I only clean it every few months.

I think sumps work well for larger tanks. It allows you to automate some things that can become cumbersome with larger tanks and gives you a place to centralize stuff. I have a 29gal sump on my 150 gal tank. Most all the equipment is in the sump or under the stand - another reason sumps work well for large tanks is there's usually lots of room under the stand. I still do manual water changes because that's when I vacuum the tank, but water top-off between changes is done in the sump. I have two returns driven by one pump that is teed to the returns. I have my CO2 reactor on one return and the UV sterilizer on the other. That way they only see half the water flow.

Sumps and canisters both have their uses. You just have to decide which is the best fit.

David

[Ozymandias]

I think what dave said is probably correct and with you tank being around 120 gal (i think correct me if i did the math wrong). you would probably have a fine time with the sump. but i would suggest that you look at how long your CO2 lasts, if it last you say a couple months (3 months in you case) i would say no big lead but if it is only a month i would say that it would an issue then.

[Pomacanthus]

Originally Posted by SCMurphy

I use sumps on my tanks as reservoirs to keep the evaporation from showing in the tank. The sump in this case is not a filter and with the way I constructed the 'overflows' there is minimal chance to degas CO2. Wet/drys are intended to do a biological filtration, are they not? That is what we use the plants for so a wet/dry actually competes against the plants.

Hey can you elaborate a bit on your overflow design?
Much appreciated POmacanthus

[SCMurphy]

I use a 20 high as a sump/reservoir with no partitions. The ends of my overflow plumbing are made of the ribbed flexible hose you see in garden centers for ponds and they go to and across the bottom of the sumps. I see much less bubbling this way rather then ending the PVC in the sump. This also reduces the 'resonance' of the PVC so there is less 'waterfall' sound. This also prevents a lot of CO2 degassing from the sump. I go through a 20 pound tank feeding 4 aquariums in about 6 months.

I allow the surface of the tank to be moved a little by the return, which helps clear dust and those films that appear in new tanks.

This is how it works.


This is the extended design that I use.


This is the best thread on the subject.

[Pomacanthus]

Hey thanks for nice images, very helpful. Question thou - doesnt the pumps rate of return (gallons per hour) need to exactly match the drains flowrate into the sump? to maintain a constant tank level? Also has this ever failed you in any way? I was originally thinking of a tradional overflow box with a gate valve (on drain) that way you could "control" the drain and let the water level in the overflow "ride high" say 3/4 of the way inside the box, minimizing Co2 loss, keeping water level constant, and still have some surface extraction. Just an idea, Im still working out design issues, but dont want too much Co2 loss.

[Gad]

I prefer canisters myself. My experience with sumps is if it can go wrong it will.

[Aqua Dave]

If you're using a regular overflow box with drilled holes for the drain and return do a search on "durso standpipe" or checkout this link to All-glass' Megaflow system. I have a 150gal All-glass tank with the Megaflow standpipe and it works nicely.

http://www.aqueonproducts.com/produc...w-overflow.htm

David

[Pomacanthus]

Gad-
Sumps and/or wet/drys are foolproof, catastrophic failures are non existant. The ONLY failure point on a gravity system is the drain - and in 20 yrs Ive never had one plug. In saltwater I stack mine with an aquaculture product that is square and rigid (biomedia) It virtually can not plug - I should clarify Im talking about an internal gravity based box with a hole drilled in tank. SIPHON boxes might be what you are thinking about - they are based on a siphon principle which is prone to failure no matter how well they tell you. They may run for years and years without incident but the design is bad no matter how you configure it, Newton was right about the apple, gravity always works the same way, every time, very predicable. The system in the thread above scares the heck outta me but i havent had time to really wrap my head around it.