Sump - Baffle placement

[mmittlesteadt]

Just throwing this out there for some ideas/suggestions...

I have a 40 gallon display tank in my living room with a 65 gallon sump in my basement right below the DT. I'll have the plumbing to the sump done tonight and then planning out how big each chamber should be and how high to make the baffles. Never made a sump before, but I did a search here (and elsewhere online) and have read a lot about them and have a pretty good understanding of them.

I am not worried in the least about flooding, with either my display or the sump. I'm running a herbie with dual 1" PVC for drains and a 1" return, (Main drain having a gate valve, emergency wide open and a gate valve on the return line). Lots of room in the sump to handle almost half the DT volume, although worst case scenario is that less than 8 gallons would drain down into the sump should my power go out.

With my 65 gallon sump I have a tank that is about 24" high by 35" long with a width of 17". I'd like as big a refugium as possible (for pods, mangrove, chaeto, live rock, sand, etc.). I will have an ATO in place and have yet to determine just how much evaporation will take place.

I'm thinking about a drain chamber housing my Eshopps PSK100 skimmer (operating water level of 7" to 11") but want to go higher than 11" as I can build a platform to raise it if needed, which will then accommodate a larger skimmer down the road if I need to replace it with a different (larger)model. Maybe a 12" baffle for the first chamber?

Then the refugium will be in the middle with the return section housing an Aquatop 3600 (1065 GPH) pump, and with my 9ft. head will give me my desired 400PGH. I also realize pumps can burn out/fail so I want to be able to accommodate a larger pump down the road if it needs replacing. Not sure how big to make my return section yet. I'm thinking about a 5 gallon RO/DI container for my ATO (easily refilled) that will be up higher than the tank and be gravity fed.

Also, not sure if I will need or want a bubble trap. I'm thinking with a Herbie and a total siphon main drain that I will not have a ton of bubbles to deal with (although I can't account for the bubbles the skimmer might produce). If I did use a bubble trap is just a single baffle (same size, but raised higher than the return's baffle) sufficient? I've always seen two baffles, which I don't understand why that is necessary. If the water from the fuge has to go under one baffle and raise over the top of the return's baffle, isn't that enough to trap bubbles?

Just curious...lots of thoughts and I'm open to ideas and suggestions. Apologies for being so wordy...just want to be as descriptive as possible for assistance.

 

[mmittlesteadt]

No replies yet. I'm finishing the plumbing to the sump today and I want to get the baffles measured up so I can get those cut.

 

[sleepydoc]

It sounds good overall. Your sump will hold about 2.5 gallons/inch of depth, so if you're only worried about 8 gallons, you shouldn't need more than 4" of extra depth at the top, you can easily increase it to 6 if you want extra room.

You don't give your proposed widths for the various chambers, but a larger return chamber will not only accommodate a larger pump should you need it, it also gives a larger buffer for evaporation if you forget to fill your ATO, or if it fails.

You have to be careful with gravity fed top offs - float switches are somewhat prone to failure. Even if a failure doesn't cause a flood (or one that causes a problem,) it can cause severe swings in salinity.

Re: a bubble trap, with the flow you're proposing and the fact that you go Drain - fuge - return, they likely won't be a problem. Most bubble traps I've seen are Over-under-over. In a previous sump, I made it simple over-under and observed that the water tended to flow under the 2nd baffle, then along the floor of the second chamber and up & over the baffle to the return section, leading to stagnant areas in the middle section. If you want to have sand in the refugium, it will potentially creep under the 'under' baffle.

If you make it under-over, bubbles could get pushed down from he skimmer output under the baffle. In reality, just a single baffle is probalby fine, though. I would just build it with one baffle and test it out to see how it works.

 

[fustilarian]

If you do use a bubble trap, make sure they are spaced out wide enough for the flow you plan on having. I didn't do that and when the pump is on full blast the water cant go thru the bubble trap quick enough and goes over it as well as thru it and out the top with enough force that it causes cavitation and bubbles right in my return section. dammit self

 

[mmittlesteadt]

Thanks for the info.

This is what I'm thinking for chambers (65 gallon tank is 17" wide front to back in all cases)...

Two baffles only (no bubble trap) dividing sump into 3 chambers...

1st Chamber - drain/skimmer area - 9" long X 15" high (9.9 gallons).
2nd Chamber - The Refugium - 16" long X 14" high (16.5 gallons).
3rd Chamber - Return - 9" long X 14" high (9.3 gallons)

My Eshopps PSK100 skimmer operates between water depth of 8" to 10" inches, but I will raise it up.

I'm open to suggestions...make the return smaller, drain/skimmer smaller (I can go narrower with both) making the refugium larger? Height seem OK for baffles? I'm thinking the second baffle between the fuge and the return an inch lower than the drain/skimmer baffle will minimize water drop and noise.

At those baffle heights I still have a little over 23 gallons of empty space for back fill should the power go out, although with my drain and return lines the way they are, I'd only fill about 1/3 of that remaining space. I'm not overly concerned with having wasted space. I'll never use the 65 gallon tank for anything else anyway.

 

[Vinny Kreyling]

Herbies do not produce any bubbles unless the water drops to the siphon tube.
Baffles usually place the water level @ about 1/2 the sump volume allowing plenty of room for whatever.
I have an 80 gallon 24 x 48 x 16 & use 1 foot for the chaeto & the rest for everything else.

 

[mmittlesteadt]

Still looking into the right placement/size of my baffles. If I make the 1st drain/skimmer section 7" long and 15" high, that gives me plenty of room to work with my skimmer (I'll have to raise it, but I prefer that anyway). That would be 7.7 gallons.

The 3rd Return section would also be 7" long but 14" high giving me 7.2 gallons. If the water evaporated all the way down to the top of the pump I'd lose about 5 gallons. I'm going to use a 5 gallon bucket for my ATO and plan on making 5 gallon water changes weekly, so that size would work for me and give me some protection from running my pump dry (not knowing my rate of evaporation) if I were to be gone for an extended time and the ATO failed.

That will leave the center section 20" long, giving me a 20 gallon refugium. I plan on adding dry and live rock and sand to this refugium, as well as mangrove and chaeto.

The sump will essentially be about 36 gallons of additional water volume to my 40 gallon breeder (which with displacement of rock, sand, etc. probably gives me about the same volume as my sump). So I'll have about 70 gallons of total water volume with a 40 gallon display tank.

Any thoughts on my baffle size and placement? Drain/Skimmer, or Return sections too small if I got a bigger/different skimmer and/or return pump down the road?

I'm trying to think of every possible failure/replacement scenarios, rather than just what might work for me now. Will this work in the future with different equipment?

Thoughts, ideas, suggestions? Anything I might be overlooking?

Thanks.

 

[mmittlesteadt]

I have the plumbing done up to the rim of the sump. Still need to determine baffle spacing and height, so the plumbing into the sump is not done yet. The return plumbing is not glued in place yet as I'm still determining best pump location (dependent on choices with baffles).

Yes, I have ball valves for now. They will be replaced with gate valves in the future. So there are no unions. For now I will just use braided vinyl hose and hose clamps. The ball valve for the drain is a 1 1/4" on the 1" line. Since the pump has a 3/4" outlet, I'm going to just use a 1" ball valve on the 1" line. All can easily be replaced if need be.

Foamcore board is taped in place to give me an idea of where to put (and what dimensions) the 1/4" thick glass baffles. The left one will be 15" high and the right one will be 14" high.

1st Chamber (on the left) will be my drain/skimmer section (7.7 gallons), the middle will be my refugium (20 gallons) and the last one on the right will be my return section (7.2 gallons). The return section also has my HOB HOT Magnum that will only be used for carbon/GFO if need be. Skimmer needs to be raised more if I keep the 15" baffle height.

 

[rickztahone]

If it were me, I'd put the return pump in the middle compartment and the fuge where you currently have the return pump. This way, you can T off the return to feed your fuge. As it stands, the drain section will overflow to the fuge and being that the second baffle is just an inch shorter, it will overflow over to the return section. However, this may cause your water to be more still than it should for a straight through sump. With the fuge on the side, it doesn't matter if the flow is much slower in that section.

 

[mmittlesteadt]

It's my understanding that T'ing off the return line for the refugium reduces the pump's output to the display tank, correct? I'm not going to buy a bigger pump for now, and I'm already dealing with a 9 ft. head as my sump is in the basement.

So, to keep the flow going throughout the refugium before entering the return section (rather than flowing more directly from drain to return), should I place a higher baffle (with space under it) before the return's baffle? This would cause the water entering the refugium from over the drain/skimmer section to have to go under this baffle before coming up and going over the return's baffle, right? This would force more flow throughout the refugium, wouldn't it?

 

[CuzzA]

Either way will work fine. My only tip would be to angle the return baffle slighlty so that water coming over the baffle doesn't create a waterfall and instead flows nice and smooth without any bubbles being created.

You may want to just go ahead and get a larger pump. Make a manifold so you can run other equipment like GAC and GFO to UV and Bio Pellets, etc. Best to do it right from the start.

 

[mmittlesteadt]

Either way will work fine. My only tip would be to angle the return baffle slighlty so that water coming over the baffle doesn't create a waterfall and instead flows nice and smooth without any bubbles being created.

You may want to just go ahead and get a larger pump. Make a manifold so you can run other equipment like GAC and GFO to UV and Bio Pellets, etc. Best to do it right from the start.

You mean angle the return baffle so the water coming over the top has a gentle slope towards the return side (baffle top leans more towards the center refugium section)? How far of an angle would be sufficient? 1/2" offset? 1 inch?

Also, I already have the pump...at some point I may upgrade. I've already stuck almost $2000 into everything (retail, although I got almost everything at cost from where I work...Ace Hardware with a huge pet department). Also for the time being I will be using a HOB canister filter for carbon/GFO (NOT mechanical filtration!). Not ideal, but hey, it gives me some reason to upgrade to new toys in the future. My wife is already about ready to kill me with what I've spent and how much time I've taken. She'll forgive me once it's up and running, and stocked. Then she'll be happy. At this point I'm still dealing with the equipment and technical aspects so she can't see the benefits yet.

 

[mmittlesteadt]

Got this from another thread after doing more searches...

"Angle the tallest baffles so the water flows over them and down on them instead of creating a waterfall like you have now. I have a 20" drop like this with 2000GPH going over a 12" long baffle without any noise.

If you look at the chart here all you need to do is angle the two baffles to the 100 degree mark and your set."

 

[mmittlesteadt]

Another option is to leave the baffles straight up and down, with the return baffle still only 1" shorter than the drain baffle, but mount a small powerhead on the return baffle and point it down and straight back at the bottom of the drain baffle, creating circulation within the refugium. Kind of treating the refugium as it's own tank with it's own circulation within it, besides the entire water flow of the display tank and sump.

 

[CuzzA]

I hear you. The money adds up fast. Just don't keep track or you might throw up.

I usually just slope them a 1/4". You just want to eliminate the possibility of a waterfall sending bubbles into your return pump. Water isn't 100% predictable, so it's best to error on the side of caution.

 

[mmittlesteadt]

I hear you. The money adds up fast. Just don't keep track or you might throw up.

I usually just slope them a 1/4". You just want to eliminate the possibility of a waterfall sending bubbles into your return pump. Water isn't 100% predictable, so it's best to error on the side of caution.

Yeah, the money does add up quick. I am fortunate being an artist and running a custom frame shop at an Ace Hardware that just happens to have a HUGE pet department with a huge amount of both fresh and saltwater equipment and livestock. They have six 40 gallon FOWLR and reef tanks and today are in the process of setting up two 220 gallon saltwater tanks. One will be FOWLR and the other a huge reef.

I get everything at cost, so while the money is adding up, I've splurged in the areas where it matters most...lighting, skimmer, RODI and tried to save in other areas where I can get by sufficiently and upgrade later. Best part is, I traded my artwork for some store credit by doing some murals in the store, so a lot of my purchases have pretty much been free to me (I get paid my regular wage while I paint in the store).

So yeah...I've "spent" a lot of my store credit already and I'm close to getting this thing up and running. But yeah...at retail? Wow, if I had to fork out this kind of money (retail prices) for a "fish tank" (as my wife likes to call it) my wife would probably kill me.

Thanks for the tip on the baffles. I realize that no matter how much planning goes into this (which I am really enjoying, rather than rushing to fill my tank and stock it) there are always going to be some surprises along the way. I'm thankful we now have the resources of the internet to do a lot of research. Back in my old freshwater days decades ago, it was an awful lot of book reading and trial and error. My experience with freshwater, while different than saltwater, has taught me the most valuable lesson of all. Patience.