Quick input needed

Hey guys,
Getting ready to start setting my baffles into my 40g breeder sump. When I had the glass cut for the baffles I changed the dimensions a bit and it just occurred to me I may have made a mistake. Take a look at the dimensions below.



The left chamber is the skimmer chamber and it needs to be 9.5" deep. The right chamber is the refugium and I've got it set to 10.5" by 12" deep. The return section is 11" by 12" deep.

Originally I had the return section set to 10" deep but increased it to 12" because I will be using an external pump and needed to drill the drain hole 3.5 inches high to ensure I stay away from the edge of the glass. I was concerned that having the drain so high would reduce the usable volume in the return chamber too much to comfortably account for evaporation.

My concern though is that since the last baffle in the bubble trap from the skimmer chamber is the same height as the refugium baffle (both 12") then the water might not drain properly from the refugium to the return section. Is there a concern that the refugium and return sections both have 12" of water? Should I make the effort to try to score and cut the last baffle of the bubble trap to 11" so the water drops an inch between the refugium and the return section?

 

If you have an ATO I would move the 12" baffle over to the refugium and the shorter one to the return section.
My sump is similar but I made my refugium almost the height of the tank to get maximum volume, it overflows to the center section so the possibility of a flood isn't an issue.

On the over-under-over baffles I made the two over baffles the same height or else the shorter one is always submerged and doesn't do much.

 

If I understand correctly, it seem that the water is coming in from the left and the right, then exiting via a return pump in the center. If that is the case, the problem you have right now is not that it won't overflow into the return, but rather that your skimmer section is going to have 12" of water, not 9.5".

The reason is that as you know water flows via gravity, so the second baffle on the bubble trap also needs to be 9.5" otherwise it will keep all of the water in the skimmer section until it reaches 12". The easiest way to fix this would be to cut the 12" baffle to 9.5".

You could also switch the 1st and 2nd lower baffles of the bubble trap and just put the skimmer on a 2.5" platform made of eggcrate and PVC pipe to avoid your concern of losing water volume in the return section. You would just need to make sure you have enough room to remove the cup from the skimmer.

Having the refugium at 12" won't matter because it will just overflow into the return as water is pumped in- the only thing you have to do is keep the total water volume low enough, that it is less than the baffles on each side of the return. So if you're skimmer section is 9.5" and the refugium is 12", the return water level will need to be less than 9.5".

 

Yeah, thanks for the quick replies guys... I had a total brain fart and screwed this up.

Yes, the water will flow from both the left and right sides, into the center... that was the plan.

Unfortunately, I can't raise the skimmer as the stand is too short... I BARELY have enough clearance as it is to get the skimmer out of the sump for cleaning. If I raise it at all, I'll never get the cup out.

SO... since I MUST keep the skimmer chamber at 9.5" of water, this means I'll need to cut the left baffle of the return sections down from 12" to 9.5". Is it OK for it to be the same height as the skimmer baffle?... both at 9.5"s?

 

Whatever the height of the left baffle in the return area is will be how high the water in the skimmer area will be. Both at the same height will be what you want.

 

Yes, the water will still overflow if both baffles are the same height. The problem only exists when the second baffle is larger than the first.

 

ok thanks guys... so this means that I now have 7.9g of total water in my return section.

I'm running 1.5" return plumbing to an external pump. As I understand it, I must keep the water at least 2" above the pump intake level. So, the top of my 1.5" bulkhead will be about 5" above the bottom of the sump. 2" above that would be 7" which means I'll only have 2.5" of space to allow for evaporation. That's just over 2g of water. I will have an ATO system in place run by my APEX... will be dosing Kalkwasser through the ATO system as well.

Seems VERY small to me. Can I install a downturned elbow on the pump intake inside the sump? If I put a 1.5" street elbow in there turned down, this would take the water intake level from 5" to 1". Will that cause my pump problems since it adds headpressure on the intake side? (it's a reeflo blowhole 1450 pump).

If I did the downturned elbow thing, I also wouldn't be able to add a pre-filter on the pump... is that an issue as well?

Sorry guys, this is my first tank so apologize for the newbie questions.

 

No worries! At least you are asking questions! So many people don't and then learn the hard way.

Unfortunately, I have VERY little knowledge on pumps, so I am going to duck out of the convo, but here is a bump for you...

 

I might have some concerns, but need more info

Questions:

- What is the main tank size?

- What pump are you going to use?

- What is the height from floor to top of tank?

 

DT is a 120g high ( 24 x 24 x 48 )

Pump is a Reeflo Blowhole 1450... will start with it set at it's lowest setting which is 812gph at 0 head. I expect 5' of head so it would be around 620gph at that pressure. Also, will be running a carbon reactor and GFO reactor as well as feeding my refugium from a manifold on the return line so the actual DT won't be receiving all of that 620gph.

Top of the tank would be roughly 50 inches (27" stand, 24" tank but the tank sets down in the stand a bit.)

There's a lot more detail in the first post of my build thread (in my sig) if you want to take a peek.