Will this external pump set-up work?

[Oughtsix]

I have run a Jaebo DCT 6000 pump externally with out any additional cooling for years without an issue. I doubt you will need to submerse your DCT 8000 just to keep it cool.

The DCT pumps are designed to be sump pumps... as such they have a decent head pressure as they need to move water up several feet in their typical configuration. By hard plumping your DCT into and out of your tank the intake pressure is going to be much higher than if the pump were in a sump and the intake pressure will balance out the head pressure. In other words your pump is going to be doing a lot LESS work than if it were in a sump configuration. In your purposed configuration the pump is going to just be creating flow instead of doing the hard work of lifting water from a lower level to a higher level. I would run your DTC externally without any extra cooling... after a couple days put your hand on the pump and see how warm it is. It should not be and I doubt it will be anywhere near hot.

The only thing difficult about an external pump is that you have to make sure your hose connections are secure and water tight. Submersed a pump that leaks a few drops around the outlet hose is no big deal and will never be noticed... with an external pump those drops add up pretty quick. This shouldn't be an issue... just something to look out for.

 

[islandguy11]

I have run a Jaebo DCT 6000 pump externally with out any additional cooling for years without an issue. I doubt you will need to submerse your DCT 8000 just to keep it cool.

The DCT pumps are designed to be sump pumps... as such they have a decent head pressure as they need to move water up several feet in their typical configuration. By hard plumping your DCT into and out of your tank the intake pressure is going to be much higher than if the pump were in a sump and the intake pressure will balance out the head pressure. In other words your pump is going to be doing a lot LESS work than if it were in a sump configuration. In your purposed configuration the pump is going to just be creating flow instead of doing the hard work of lifting water from a lower level to a higher level. I would run your DTC externally without any extra cooling... after a couple days put your hand on the pump and see how warm it is. It should not be and I doubt it will be anywhere near hot.

The only thing difficult about an external pump is that you have to make sure your hose connections are secure and water tight. Submersed a pump that leaks a few drops around the outlet hose is no big deal and will never be noticed... with an external pump those drops add up pretty quick. This shouldn't be an issue... just something to look out for.

Thx a million for the info Oughtsix, great to get a different perspective. I've seen a bit of debate about whether the Jebao's can be run externally -- the sticker on the back of the pump says "Must be run into water." but I don't know if that means water must be run through it or if it's broken English and means "Must be run in water (submerged)." Also it's always quite hot where I live (80-90's just about every day of the year), which is why I was thinking to put it in some kind of water reservoir. Besides damage to pump I am concerned about raising water temp in the tank because all my tanks are already running at pretty high temps, can't avoid it here unless you want waste a lot of money running an A/C 20 hr a day, which isn't good for human health.

But your experience gives me some confidence to at least try an external/dry approach with the DCT, while monitoring both pump temp and tank temp. I'll put the pump on a piece of tile in a plastic tote and throw in a water alarm just to be on the safe side.

Btw, on the return lines I'll be using 3/4 pvc -- what size would be recommended for the intake? Would 1" be OK or perhaps 1.5"?

 

[BichirKing]

on my dct-6500 I have 1.5" in 1" out. I tried it externally first on my sump and didn't really notice any heat. I put it in the sump just to make it more compact under the stand.

 

[Oughtsix]

The Jebao pumps are magnet drive pumps... so there is no drive shaft coupling a motor to the impeller. This means that the the impeller and your tank water are very isolated from the drive coils and there will be very little heat migration into your tank water.

You said your plan is to use the pump to run a UV sterilizer and your overhead filter. UV sterilizers have a max flow raiting. If you exceed the max flow rating for your UV sterilizer the water will not be bathed in the UV light long enough for the UV light to do its job. I think your problem is going to be too much flow instead of not enpough flow. I would run 1" tubing in and 3/4" inch tubing out. I would put a T on the 3/4" output and run one side of the output through the UV sterilizer then back to the tank and the other side of the T to the overhead filter. I would put a valve on the UV side of the circuit so you can cut down the flow through the UV sterilizer and force more water through the overhead filter.

If you wanted to maximize the flow then 1 1/2" in and 1" out makes sense. But that is not what you are trying to achieve.

My daughter has an Axelotl... we had to get a water chiller to keep it in it's comfort zone of about 62 degrees in the summer. It does a good job and is a lot cheaper than running theair conditioner 24 hours a day.

 

[islandguy11]

The Jebao pumps are magnet drive pumps... so there is no drive shaft coupling a motor to the impeller. This means that the the impeller and your tank water are very isolated from the drive coils and there will be very little heat migration into your tank water.

You said your plan is to use the pump to run a UV sterilizer and your overhead filter. UV sterilizers have a max flow raiting. If you exceed the max flow rating for your UV sterilizer the water will not be bathed in the UV light long enough for the UV light to do its job. I think your problem is going to be too much flow instead of not enpough flow. I would run 1" tubing in and 3/4" inch tubing out. I would put a T on the 3/4" output and run one side of the output through the UV sterilizer then back to the tank and the other side of the T to the overhead filter. I would put a valve on the UV side of the circuit so you can cut down the flow through the UV sterilizer and force more water through the overhead filter.

If you wanted to maximize the flow then 1 1/2" in and 1" out makes sense. But that is not what you are trying to achieve.

My daughter has an Axelotl... we had to get a water chiller to keep it in it's comfort zone of about 62 degrees in the summer. It does a good job and is a lot cheaper than running theair conditioner 24 hours a day.

More great info....And yes agreed, I am also worried that this pump might be a bit too much, even dialed down. I would prefer to have a DCT or DCP-6000 (in fact I bought a DCT-6000, the box says DCT-6000 but inside was a DCT-8000 lol and I honestly can't remember where I bought it to try and exchange).

So was planning to set up almost exactly as you describe above -- but also I was thinking to make a 3rd line off the return beside those going to UV and OHF. This 3rd line (hose) would go directly into the tank if needed to take flow away from UV and OHF. I could also pull it out when doing water changes and connect another line to drain the tank.

Going to get on this project later today, will post a pic or two when done.

 

[DN328]

I agree with Oughtsix too.

I would consider running the Jebao for your UV like a closed loop circulation pump. Although not Jebao, I have used and currently use DC pump for my CLC now. The fact that you will have it turned down for the UV and not submerged is not a bad thing too. This will help keep the heat down.

Let me know if you'd like a visual of how mine is set up.

 

[islandguy11]

Game on! (just trying to psyche myself up for this little tank upgrade project -- I'm engineering-challenged, so I'd be shocked if I didn't run into an issue or three (or take 5 hr to do what most here could do in 2 hr lol).

I agree with Oughtsix too.

I would consider running the Jebao for your UV like a closed loop circulation pump. Although not Jebao, I have used and currently use DC pump for my CLC now. The fact that you will have it turned down for the UV and not submerged is not a bad thing too. This will help keep the heat down.

Let me know if you'd like a visual of how mine is set up.

Great to hear others using DC pumps successfully/safely in this manner, Thx for feedback. And you bet, would be great to see any pix of your (or other's) CLC set-up, please share when convenient.

At this point I'm thinking to make a combo pvc piping and hosing system -- with hosing in some sections it would give me the option of looping it or whatever to increase head pressure, which is actually desired in this situation with a somewhat overly large pump. I can replace the pump later, but will make do with that one for now as I also have to set up a similar system for another 325 (based on learning from this one).