Velocity Pump Modification

[quikenuff]

Hello All,
I’ve been reading the RC forums for some time now. It wasn’t till I went to a local fish shop here in Tampa FL looking for a new return pump that I thought I had something worth posting. I searched to forums for a similar post and didn’t find one so here goes.

The situation: I have a 155 AGA Bow front tank that I recently switched from FOLR to a reef tank. My current pump a velocity T4 (A.K.A Poseidon PS4 and possibly some other names) is extremely quiet but adds about 2-3 degrees of water temperature to the over al system. After the switch from PC lighting to MH my water temperature was pushing 82 F at the end of my lighting cycle.

I was trying to find a pump as silent as the velocity w/o adding the heat. John at “Fish and other Ichthy stuff” suggested running 2 velocity pumps to get the flow I needed for a reef tank until I explained to him my excess heat situation. He suggested added a cooling fan to the pump before spending the money on a new pump. Taking his advice I decided to post my modification to see what other thought, or to see if there could be a better way to modify the pump.

Materials used
• Velocity T4 external pump
• OEM Intel P4 CPU cooling fan and heat sink
• 80mm AC fan
• 4 nuts and bolts from home depot

The Modification:
First I removed the stock fan from the heat sink and installed the 80mm AC fan. I used a little loctite on the treads to make sure they don’t vibrate loose.
http://reefcentral.com/gallery/data/500/1459781.JPG
Then I removed the rear housing of the pump. I drilled a small hole in the housing to feed the fan wiring in. Inside there were screws holding the positive and the neutral wires on the power cord witch I used to supply power to the AC fan.
http://reefcentral.com/gallery/data/500/145978SNC10074.JPG
After securing the positive and neutral wires with the screws I reattached the rear housing. I used zip ties to mount the fan to the pump and a little thermal heat sink compound on the mounting surface on the heat sink. I also used a little silicone to make the hole I drilled water tight. Here is the finished product.
http://reefcentral.com/gallery/data/500/145978SNC10075.JPG

Anyone else try something similar, any suggestions? I will post overall temperature changes if any, in a couple of days.
Thanks,
Quik

[prugs]

The velocity/poseidon pumps are designed as water cooled pumps. You may have some benificial cooling with your mod. But you would gain a lot more cooling effect by having the fan blow on the tanks water than the motor housing.

[quikenuff]

Agreed Tom, I have four 3" or 80mm fans blowing across the top of the water now. I have about 2 - 2 1/2 gallons of evaporation a day. I could add more fans to the canopy but I thought I would try this first. The intent of the mod is to counteract the heat the pump adds to the tank in the most direct way possible. I know most would suggest getting a chiller at this point but that's not an option right now.

[quikenuff]

It doesn't look like I generated much discussion with this topic. Possibly with good reason, the modification was a bust. No noticeable change in system temperature after installing the mod.

[RWillieK]

I did something similar, and noticed a nice difference.

I used three smaller heat sinks, getting more surface area than your larger one.

I dropped the temp of the brass screw on the top of the pump (I used that as a reference) by 8 plus degrees.

I'm running three 26mm fans on a cell phone charger/convertor.

I also put a quirt of thermo transfer paste under the heat sinks.

Robbie

[quikenuff]

Thanks for the feedback RWillieK. The increase in surface area does make sense. Did you get any noticeable temperature drop in the system itself or just from the pump?

[RWillieK]

I didn't monitor the system long enough to see, I was more concerned with have one control - the brass screw was mine.

Robbie