My DIY sump/refugium.

[dberrong]

OK. I finally got the leaks fixed in my donar 30 gallon glass tank. I have a few questions for everyone to give me some ideas on. The tank is 12" wide and 17" tall. I had 4 baffles cut 12x13. I plan on using 3 on the left side of the tank as seen in the pix. This small compartment will house my protein skimmer and UV sterilizer. The middle section will be the refugium. The last section will house the return pump. I chose to use baffles that were the same size to keep the return pump section fairly low in water volume instead of allowing the refugium water to be part of that section in case I ever lose the siphon from the overflow, the pump will have a minimal amount of water to pump into the tank, thus keeping the tank from overflowing if there ever was a siphon malfunction. I'm pretty much building the sump that Melev showed me on his website. My first question is if everyone thinks if using the same height baffle for the last column is a good idea? My second question would be how wide should I make each section? My thinking is the return pump section should be as small as possible with the refugium being as large as possible. Is there a rule of thumb for the section overflow section that will house the skimmer?
Those baffles are just sitting in there. They aren't siliconed yet so don't stress about their positioning. :)

[melev]

That looks like window pane glass, which is 1/8" thick and very brittle. I would recommend you use 1/4" glass, and make sure the panels are 1/4" less than the width of the tank. You want 1/8" gap on each end to avoid stressing the outer walls, or risk having the sump burst. (Yes, this has happened to several people, not realizing it might be a problem.)

If the return section is too small, it will either #1) suck the water out too quickly and then pump tons of bubbles into the tank, and/or #2) run out of water due to daily evaporation too quickly and pump tons of bubbles into the tank.

I would divide the sump so that there is enough room for the skimmer, then divide the rest of the sump in half - 50% for the refugium, 50% for the return.

If you want to make the water level share between the return and the refugium, make the final baffle shorter and secure some eggcrate above it. As pictured on this page:
http://www.melevsreef.com/acrylics/sumps/glass/

[dberrong]

That makes sense. I do believe that it is 1/8" glass. I live in the Mountains, and we don't have one of those local glass shops. :) I'm going to try this and if it cracks, I'll make the 30 min. drive for thicker glass. The 12" is roughly a quarter inch shorter. Well, maybe more like an eighth inch, but it clears both sides as I place the glass in the tank. I'll post more pix as I make progress on the tank. I'm going to let it sit in water for another day or so just to make sure this thing doesn't leak on me.
How many gallons evaporate on average a day??

[melev]

That varies from tank to tank, based on ambient temperature, humidity levels, altitude, fans blowing / ventilation, and even a/c vs heat.

[dberrong]

That makes sense. Thanks.

[dberrong]

I drained my tank so that I could dry it and silicon in the baffles. Once it was dry and I placed the baffles in the tank, there was plenty of room at the bottom of the tank, but at the top the baffles hit the sides of the tank! I measured the tank when water was in it. Now my baffles do not fit without me pressing the sides of the tank out. Are tank usually wider at the bottom to allow for water pressure at the top??? What should I do. The baffles were perfect when water was in the tank!!

[melev]

Your baffles are too large, and I would not use them.

[Grue]

I went a different direction with my baffles. Seeing as they are there to direct the water, I felt they were not realy ment as a secondary structure. And as such low strength was required. Yes it had to be strong enoulf to withstand incomming and exiting pressures, but not to keep it from leaking on the floor. Because of this and the expansion and contraction of the glass, I chose plexiglass for my dividers. The thermal coeificents of plastics make it a better divider (IMHO). Aquarium sealants will stick to it but not really bond. (Yes, still water tight) As the silicon adhears to the glass if basically makes ramps to hold the plexiglass in place. IF there were to be some massive heat buildup in the tanks the plexiglass would bend before the glass breaks. I have uploaded pics in my area for anyone to pick it apart Any critism (yes even bad) is appreicited My 2 Cents BTW Merry Christmas to one and all ;)
Grue

[dberrong]

That may be my best bet. I'll trash the glass baffles since they are too large. Oh well. Live and learn. At least the tank isn't leaking! ;) Merry Christmas!