Question for Larry M and other DIY sump builders

[RWD]

I'm getting ready to build my first acrylic sump and need some ideas. It will be 35" long x 22" wide x 16" tall so that it fits in my stand. I plan on keeping a DAS BX-2 skimmer and 2 heaters in the sump.The return pump is a external Little Giant pumping about 1000 gph back to the tank. Larry's sump for his 135 looks like what I'm trying to do except for the refugium.
http://www.reefcentral.com/northernreef/miscphotos/135sump.jpg
. ----------------Larry's Sump above-----------------


Right now I'm using a Rubbermaid container with no baffles which leads me to the problem. I can't get rid of the bubbles from the skimmer and/or the corner overflows. The overflows dump into the sump with great force (1000 gph) and so the bubbles never get a chance to rise. The skimmer output is as far away from the pump intake but I still get microbubbles. I have also went over all the plumbing joints hith silicone to seal any potential air leaks on the intake side of the pump. I'm going to scrap the Rubbermaid and build asump with baffles.
Larry and others,
How is you sump working and if you could change anything, what would it be.(add more baffles?) I noticed that the first baffle the water flows over it. Do you think it would be better to have the water flow under it instead? It seems that there would be less air/water mixed lower in the sump. Also, I noticed you didn't use any bracing around the top of the sump. Is it strong enough so that none is needed?
Thank's in advance. I have read all the stuff on your site about sumps and acrylic and it's been a big help. Bob

[Yam]

I'm using a rubbermade sump also. To help dissipate the bubbles, I zip tied a large food bag onto the output of the overflow in the sump. The whole bag wasn't tied to the pipe, but only a small corner of it was. The water hits the bag, and goes back in the opposite direction because of the food bag giving extra time for the bubbles, and also slowing the water velocity. Kind of like a large pipe, slow velocity, but large volume.

Danny

[Snailman]

Look here -> http://archive.reefcentral.com/vbulletin/showthread.php?threadid=8051 for some solutions to you rubbermaid bubble problems.

[shadetree]

RWD,

I think the first baffle is more efficient if the water has to go under it as you mentioned. The side of my sump where the water enters is also slanted towards the baffle. Make sense? When the water enters the sump it is above a slanted bottom. The water and any bubbles have to go below this level to pass under the first baffle. I also have 1" pvc in the bottom of my bulkheads that enter the sump. On the end of them each have a T with an L on each end.
|......|.|..........|.|-returns from overflows
|------| |----------| |---------|--water level in sump------
|..|..||.||..|..|..||.||..|.....|
|..|_________|..|_________|.....|-first baffle
|...............................|
|...............................|.....|
``````\.........................|.....|
````````````\...................|.....|-second baffle
``````````````````\.............|.....|
````````````````````````\.............|
``````````````````````````````\_______|_____________________

Hope the scribble above helps.

Scott

ps I can't seem to get the spaces to work with my diagram. Any suggestions would be appreciated, I will try to decipher it for you when I find out how.

[Edited by shadetree on 10-29-2000 at 07:08 PM]

[RWD]

Yam and Snailman,
I have tried those ideas and a few more. No matter what I do bubbles make their way back to the tank. My old tank with half the gph through the sump was perfect. I think it's the fact that with 1000+ gph there needs to be more dwell time. I worked on the new sump yesterday. The basic box is done and now I need some suggestions for the # of baffles. Is 4 enough? I now see why Larry has the water flow OVER the first baffle. It sets the water level of the first chamber. If water went UNDER it the water level would rise to the top of the second baffle.
Shadetree,
I don't fully understand what you are saying. The diagram is a little hard to read ;) I get the part about the tee's with elbow's and I may try that.Thanks
Bob

[Snailman]

RWD... That amazes me how that is happening. :confused: We have 2000 GPH going into our bucket and all of the bubbles are on the surface of the water and gone before they get 4" from the bucket. As far as the baffles, I think that it should go over the first baffle (just like a square bucket) because if it goes under it the submerged air will get sucked into the area between the first and second baffle.

[RWD]

Snailman,
I actually read your reply in the other post and tried the bucket trick (I also tried a small fish tank, foam blocks, a acrylic baffle wedged in the sump,various plumbing tee's, moving the skimmer around, etc)lasts week but it didn't work. The rubbermaid sump is only 30(?) gal and I could only get a 2 gal bucket in there. I'm sure your suggestion would work if I had a 150 gal sump like yours but that's not the case. At any rate I'm scraping the Rubbermaid container and going ahead with the acrylic sump. Thanks for your suggestions, Bob

[Yam]

I think half of the problem lies in the Durso standpipe. I have tried this method, but found it to be too troublesome. It sends way too many bubbles into the sump. Its also very tough to get it working with a surge device. And also, I had a snail get into the pipe, almost flooding my tank. Why not just use a gate valve and back up the water in the overflow. With the Durso, or the gate valve method, you still need a way of preventing snails from getting into it. I've had snails go out of the water and into the overflow area. What I would suggest is to cap off the stand pipe and drill hundreds of 3/8" holes into it. This way, anything small enough to fit through the hole will still be able to pass through the partially closed gate valve.

I think the most important benefit of the Durso method is that it allows you to adjust the flow without restricting the pipe, allowing larger things to pass through. A simple pipe with holes drilled into it will prevent things from getting inside and having the same effect. Snails can still get inside the pipe, but not necessary flow straight through into the sump, possibly flooding your tank, thus the need to prevent them from getting inside in the first place. Just don't glue the pipe into the bulkhead fitting, and every month you can easily pull it out (if you are using a bulkhead w/ slip fittings) and clear out the holes. Takes about 5 min. IMO, this is just as effective, and not so touchy.

BTW, I couldn't find the address of your webpage, but I'm assuming you have two independent overflows? You would leave one of them running at full capacity, and the other one more or less dry. This way, if the first backed up, the second could handle all of the flow by itself. A 1" bulkhead can handle at least 1000gph (without too many kinks going into the sump).

[Toast_Man]

I had a similar problem with my tank.

What I ended up doing was making a bubble trap of sorts out of a couple of CD "spindle" cases. These cases are like large plastic cups aprox 6" in diamiter and they are used to store bulk CD's. I stacked two inside each other and drilled a bunch of holes in the bottom of the inside one. I then cut a hole in the botom compartment large enough to press fit in a 45° PVC fitting. I drilled some outlet holes in the top container at about an inch above my sump water level. I then filled the top portion with LR rubble and ran my sump return in to the bottom chamber

This seems to force 90% of the bubbles to vent out of the top of the container and the rest seem to stay on the surface

. = blank space

.|======|
.|******| <---holes here for outlet (* = LR rubble)
||******||<---aprox sump water level
||******||
||--------||<-----bottom of top container is perforated with a large number of holes
|.............|
|.............-
|.............-<---- inlet from overflow
|---------|


hpefully the above ASCII scribble will help explain things better

HTH

Joel

[RWD]

Yam,
I do have two corner overflows using the Durso pipes. I have tried other ways like you suggested includeing a valve to back up the overflow. It's hard to give up on the Durso's because they work so well and ar very quiet. I may try your idea with the million holes if I still get bubbles with the new sump.Good point about the snails. Since I have two overflows I figure if one gets clogged the other should handle the flow.
Toast_man,
Your idea sounds good. I may try something similar but made out of acrylic. Thanks for the idea.
Bob

[Agu]

Bob,

"except for the refugium"
I have a sump very similar to the pic and it works great, mag 950 in the sump and no bubbles. I think the key is the refugium filled with macroalga. Before tha alga took off I had bubbles, but later with growth it's like the alga catchs or diffuses tha bubbles.

I've done the durso with a piece of capped pvc drilled with a bunch of holes to keep critters out. It works fine but will raise water level in the overflow by about 1/2". If you have a high level in the overflow to start with you might have to shorten the standpipe a little bit.

[Psyduck]

Are you sure the bubbles are comming from the ones caused by the overflow making their way to the return pump? I always have a small amount of bubbles, and it was suggested once that they can also come from a problem with your pump, some sort of gasket not working properly. Also, if a snail crawls into my return line, the shell for some reason causes bubbles. If you cant find your cause from the return, it may be a different problem

[RWD]

Agu,
I see what you are saying. The algae is like Mother Nature's filter floss and eliminates the bubbles. I like Larry's design but I allready have a separate refugium which is doing great BTW. The extra 1/2" won't be a problem if I go with the Yam pipes ;).
Psyduck,
I did go over all the plumbing joints a few times and even smeared silicone over evey possible seam to block any air leak but still got bubbles. It has to be the Rubbermaid sump with no baffles. I'm about half way done and I'll post when I get I installed.
Thanks everyone, Bob

[Agu]

Yeah, the algae is "like filter floss", I was going to post something like that but didn't figure any one would get it.

Agu