CSD Air Reduction Mods?

[WDLV]

I'm looking for mods to the Carlson Surge Device that reduce or eliminate the air bubbles at the beginning and end of the surge cycle.
I plan to build one soon out of a 55 gallon drum and 1.5" PVC

[WDLV]

OK so I built one. I significantly reduced the size because I knew that my overflows would never be able to keep up with the kind of volume that a 55 gallon surge device could produce. I will probably use a 55 if I have a stand alone system that is OK to have rising and lowering "tides" or if I have a system that is large enough to absorb the surge without a notable difference in water level.

I made this one out of a 5 gallon bucket using 1" PVC for the surge portion. After experimenting with different lengths of pipe, I found that two factors heavily influenced the standpipe height and thus the function of the device. One was the height from the water's surface (which I already figured) and the second was that if you only cut the bottom of the intake of the standpipe (inside the device) that the surges and refill times are significantly reduced and the bubbles are significantly increased. In my case there was basically a constant surge with a boatload of bubbles.

Something told me to put a T on the end of the pipe so that air would be sucked in quickly and terminate the surge. A few pipe height adjustments later and I was in business.
Some other things that I feel were worth noting were that the device needs to be put in motion before you can determine if the standpipe is the right height. The top of the U can be much higher than I anticipated because the flow will start before the water goes over the top of the standpipe.
However, if you do not start the flow by partially removing the stand pipe and quickly replacing it (this primes the portion below the Device reservoir) it will probably overflow onto your floor (depending on the height of the standpipe.)

The portion of the device below the reservoir should have it's output submerged fully when the refill phase is active to avoid losing it's prime.

Mine surges for about 20 seconds and refils for about 20 seconds.
Once finished I secured a lid on the bucket to limit the shoshing and gurgling sound. Now all you really hear is a small burp at the beginning of the surge cycle.

If anyone is interested, I can post pics (maybe even a video) later.

[Fearlessmoto]

how do you build a carlson surge device?, it sounds interesting, i saw the picture in one of the other threads and am intrigued by how it works.
thanks walt!

[WDLV]

I recently made a mod to mine that allowed for a lot longer surge with a lot less bubbles before and after the surge. Fill Time is now about 90 seconds. Surge time is about 50 seconds.

Start with a bucket or other water reservoir that will be either suspended above the display or sit next to it. The bottom of the reservoir should be higher than the display's water level. The maximum size of the reservoir will be determined by the volume of the display, the water level in the display when the return is not running and the overflow's ability to drain water.
Drill out an appropriately sized hole and install a bulkhead in the bottom of the reservoir.
Inside the reservoir you will attach an inverted U- tube. One arm will attach to the bulkhead, the other will end just above the bottom of the reservoir. The bend in the U-Tube must be a couple inches below the top of the reservoir or the reservoir will overflow rather than surge.
To the bottom of the bulkhead (outside the reservoir) you will attach a straight tube that goes into the display tank. Add a 90 degree elbow to the end of the tube inside the display tank.
Attach your return line to the reservoir. When the reservoir gets most of the way filled, remove the U-Tube from the bulkhead and quickly replace it again to start a syphon inside the U-Tube.
Once the reservoir has drained, check the water level in the display against the straight tube from the reservoir. You will need to drill a small hole in this tube just above the maximum water line. This breaks the syphon at the end of each surge cycle and allows the reservoir to refill for the next surge.

There are many ways to modify this setup. For example some have used a toilet flapper and float to start and stop the surge in place of the U-Tube. I may be building another soon. I'll take lots of pictures and measurements if I do.


BTW, if you have a float valve or float switch in your sump, you will need to lower it to accomodate the additional water volume. You will need an additional baffle in your sump to keep the water level constant for your skimmer. This was not necessary for me since the sumps water level only changes about 1/2" between the surge and refill cycles.
Alternately you can pull water from the display if you do not have a sump. The water level will change, but I actually find this to be desirable in some cases. Some corals and anemones have no problem with this. H. mags and many species of acroporas are notorious for being exposed during low tides with no ill effects.

[Fearlessmoto]

Thanks for the info walt, i am going to try this on my 55 gallon sump, which is also my soft coral grow tank(just set up so not much coral in there yet) i am also setting up a 29 gallon SPS add on to my system, if the soft corals take to the surge device, i will set up a much larger SPS system.

GOOD STUFF!

[WDLV]

Cool. I hope it works out for you.

The reason I did this was reinforced yesteday. One of my BTAs got sucked into a powerhead yesterday in the tank that did not have the surge device. This was one that I do not have clones of. So, I'm none too thrilled.

[Fearlessmoto]

anemone sushi, not good eats.

STUPID POWERHEADS! I dont know how many fish and anemones ive had turned into chop suey by a powerhead or pump, no matter how i try to guard them the critters always find a way to get diced up.

sorry about your anemone.

[WDLV]

Well, it could still recover. It was only one side. I've had BTAs split as a result of this kind of damage.