External Skimmer disadvantage

[invincible569]

One disadvantage that i didnt think about with external skimmers was the amount of water it will poor back down to your sump when electricity goes out. Unless you have a check valve. Think about having that BK400/500 and 40+ gallons comes rushing back down to your sump.

[Miguelito]

It shouldn't drain like that. I had a huge H&S skimmer that only put a couple gallons back, max. It drained back out the inlet into the feeder pump, but only down to the inlet.

I guess it might be different with the BK, since the plumbing is different. I'll have to make sure this doesn't happen when I figure out my plumbing!

[invincible569]

Best practice for a Bubble King is to place the skimmer higher than the sump (external). If thats the case, a check valve would work out ok.. but this is something to implement if you havent thought about it already.

[Heinz]

rise your telescope pipe and open up your wedge pipe, that will reduce the water that runs back to your sump when power goes out,

[moonpod]

Dude, your telescope pipe should be fairly high up. The "disadvantage" is not that the sump will see much water getting back into it with power failure, but rather that when it comes time to clean the thing, it ain't so easy to empty the thing.

[invincible569]

Chuck, LOL! Tell me about it! Do they hire maids who clean skimmers?

[GTR]

Chuck, LOL! Tell me about it! Do they hire maids who clean skimmers?

That's painting a fine picture in my mind...

SteveU

[moonpod]

Hey fishnets and short skirts are almost never a bad idea.

[Miguelito]

OK I'm troubleshooting my new set-up (going up next weekend) and this thread had me a little worried. My sump on the 150 is already barely going to catch my tank surface water, so the skimmer draining would put it over the top.

Here is my theory. If you have a feeder pump from your sump, a power outtage might drain the water from your skimmer back through your feeder pump. The pressure would push the water downward to the level of your pump, which is pretty low. This didn't happen on my last skimmer because the water entered the skimmer at a much higher level - which is where it drained to.

If you feed your skimmer from above, as I will do, the skimmer will only drain to the riser tubes, because the water can not flow upwards.

In the first scenario - if you use a "U" from your feeder pump, up over your sump, then down again to the Red Dragon - I don't know if the water will drain out - because it has to travel north, however, it could create a backflow syphon.

So, that's just a theory, LMK if its wrong.

[Detritivore]

fliger, it will syphon until air gets into the "U"(therefore breaking the syphon) or until the water level of the two sides (in this case, sump and skimmer) equalizes (the syphon will just stop).

so the concern is that because the red dragon is so low, it will basically drain the whole skimmer into the sump(if you are feeding it with a pump)?

[Miguelito]

Yeah - thats the main concern. That's a HECK of a lot of water. I don't see where the riser tubes come into play. The water shouldn't stop until its equalized with the sump level, or a syphon break (air comes in thru the skimmer body when it reaches RD level) - as you said. So you gotta be careful since the RD is so low.

Especially if you elevate the skimmer above the sump. If it were at sump level, it would equalize pretty quickly depending on your set-up.

Unless you gravity feed it from above.

My next thing to figure out with gravity feeding is, if the RD is turned off, will the water still be able to pass thru to the sump? I'm feeding 100% of my overflow water thru the skimmer - so essentially its just another step in the plumbing from tank to sump.

[Miguelito]

BTW thanks for the thread Edward. I'm having a sump custom built and it made me trouble shoot again. The guy was gonna start cutting my acrylic tmw and I had to have him raise the sump height 4".

[Detritivore]

if you gravity feed it from above, it will only syphon to the riser tube.

the solution to the "U" plumbing would be to drill a small hole at the bend of the "U" and connect airline tubing to it and direct the airline tubing to the sump above the water level. that way, it should allow air in if the feed pump turns off.

[invincible569]

i was also thinking about modyfying the sump and placing a large overflow that sits high up that can hold extra water.. eithe rthat or just stop it. and once it goes back down, it will release the water back into the sump. Kind of like the bowl of a toilet.