Sump - need advise on intake/return placement for sides of tank

[MattyM]

Hi all - as some may know, I'm working on a custom tank build. I initially thought I couldn't use a sump (thus my previous canister post), but it turns out I probably can! But only if the tank is drilled on the side(s). I can do a single 3/4" return or two 1/2" returns, along with the overflow. They can all be on one side, or split between both sides.

The tank will be around 65" L, 22" H, 18" deep - any advise? I'm so used to the intake being towards the bottom of the tank that I'm not sure about flow. Any tips appreciated! 

[madmark285]

For myself, I didn't think using thru hull return lines was worth the money, labor or worries. I don't trust check value, it would require another value, diamond hole saw, thru hull fitting return line(s). I used 3/4" black PVC pipe, they blended in with the background. 

I put a Tidal 75 on the side of a 29 gallon tank, it sets up an impressive circular current when on full output. So If you put your returns on the bottom, same side as the overflow box, would it create a circular current in the whole tank? And is that the desired flow you want? My barbs hang out on the bottom of the tank alot when the Tidal is at max, they just sit in the current. In the 75 gallon tank (under repair right now), they were much more active. I would at least test it before I drilled the tank. 

Not sure why you can't use 2 3/4" lines, I would at least use 3/4" until you split the flow (3/4" x 1/2" tee). 

Mark

 

 

[MattyM]

@madmark285 - yeah, that's why (at least these) sumps are drilled more towards the top. No check valves, but in the event of a power outage, since everything is drilled towards the top, the sump reservoirs under the tank would ideally be able to hold enough water so that when the water gets below the tank holes, the siphon will break before the reservoirs overflow. Those would all be drilled for me by the pros - I don't intend to mess with that stuff. But you raise some good points. I assume they do not recommend 2 3/4" drillings b/c of the size of the side panel and it's integrity. Are you recommending that b/c of stronger flow? 

Here's a much larger version of what I'm looking at (only with holes drilled in the back of the tank vs side). 

Here's someone with a side drilled setup like I'm looking at: 

 

[madmark285]

With an overflow box, putting the water returns on the top of the tank doesn't make sense for me. My overflow box creates a strong surface current, I have to use a feeding ring else the food is suck down into the sump before my fish even see it. I guess you can point them down but I prefer to put the returns low, I drilled a hole on the top of the return pipes for a siphon break.

I am in the process of putting a sump on a 40 gallon tank, I have all the parts so I might as well. As you are doing, the overflow box will be on the side. I love sumps with filter socks, so easy to maintain. 

So are you buying or making a sump? That seamless sump shown above is very pricey. I plan on using a 20 gallon tall tank for my sump, will use 1/4" PVC Trim/Sheet ($26)  or 1/2" PVC sheet ($39). Just FYI, a 4" filter sock will fit inside a piece of 4" thin wall PVC.  

On 3/4" return lines, no data but just doing what the reefers do, they tend to use 3/4" lines. You don't want to restrict the water flow and little difference in price between 1/2" and 3/4" pipe.