1/4 hp chiller on a 46 gallon tank

[randok]

I'm a bit new to newt keeping, and being in Northern California, I know that soon it is going to start getting hot for my Eastern Newts.



The question I have is, do you think a 1/4 hp chiller will be overkill for a 46 gallon bowfront? It's got about 40 gallons of water in it.



The unit I'm looking at is the Ecoplus 1/4 hp compact chiller. My main concern is that the minimum recommended GPH for a pump is 633gph!



Doesn't that sound a little high? Can I get away with using a slightly less powerful pump (say in the 475-500 range?).



I'm thinking about going this route mainly because most of the user reviews for 1/10 hp chillers say that they only get their water to be around 72-76 degrees F depending on tank size, and I really want to be able to hit 68 degrees or lower. Even if a weaker pump makes the chiller a little less effective, I'd rather do that then have a 1/10 hp chiller that has to work really hard to hit my target temps if it can hit those temps at all.

 

[randok]

Well, I decided to bite the bullet and order the EcoPlus Compact 1/4 hp unit. There was a refurb unit being sold for $325. I also decided to try out an EcoPlus model 633 / 594 gph pump. I figure that by the time the pump sends water down through the chiller and back up into the tank, it will no longer be pushing water at 594 gph into the tank after making the long trip.

Previous to this I did have a circulating fan in the tank that supposedly pushed water around at 500 gph. If the flow is similar in strength to that, then my newts should be okay and not be getting pushed around the tank all day. Of course this is all really mostly for the hot summer months (I'm in Oakland, CA - it'll reach the low-mid 90s here). If the flow is too strong, I do have a valve I can install to slow it down a bit.

Once everything is set up, I'll post my results here.

 

[numpty]

Looking forward to hearing how your chiller works out. Room temps here are already getting up to 30 C (high 80s F), and I've been pushing water through a fridge for the past few weeks ... only moderately effective! I'd take a "cheap" chiller if I could make it work.

 

[randok]

Well so far so good (and thx for expressing interest Numpty). It works very well, but it is only 74°F / 23.3°C ambient temperature where I am so it's not a heavy duty test.
I cooled the water down from 73°F / 22.78°C to 68°F / 20°C. At first it ran for about 20 minutes straight to reach that temperature, now it only runs a few minutes to maintain it roughly every 45 minutes or so.

Something odd about this unit is that it calls for a 633 GPH minimum pump, but their own brand submersible pump model 633 is rated for 594 GPH - which makes no sense to me.

It isn't super loud, but you do hear it. I ended up repositioning it so that I can't hear it as much in my room around the corner.

For the pump, I had to install the valve I had as the current was too strong for my Eastern Newts. Which makes me wonder if I might be able to use a weaker pump (300-400GPH) instead. I mean if I'm restricting the water flow from the pump with a valve, then what's the point in having such a strong pump in the first place right? So long as the chiller operates properly for an extended period of time, I may switch it out later on. I'm suspicious that the minimum GPH numbers might be more of a recommendation rather than a requirement.

Alot of other 1/4 hp chillers on the market have lower minimum GPH requirements, but none of them were as cheap as this refurbished unit.

My other complaint about the pump - it's huge! at least for a 46 Gallon / 174 Liter tank. It looks and feels clunky in my tank - like a 1970's station wagon. I'm going to have to figure out a creative way to hide it.

Oh and another thing, I'm using a U-tube return that is aimed at the back wall of the tank, and I should have also gotten a U-tube for the intake, because the 3/4" tubing does not bend well out from the top of the tank. I will get one of those soon.

All in all it's great for now. Once the weather really gets hot I'll really be able to put it to the test. Luckily I made a screen top for my tank and have a desk fan I can use as well. I'll probably switch off between the 2 depending on how hot it is and how expensive my electric bill gets.

Knowing what I know now I would still get a 1/4 hp chiller. I would have maybe spent $75 or a little more to get a unit that is rated at around 300GPH instead though. 300 GPH would have allowed me to use my canister filter with the chiller and that would have been perfect. But, I'm happy enough with this setup that I'll keep it. Later on when the heat shows up I may post my results then.

 

[randok]

Okay, I've learned a few things since my last post.

First off, I didn't like having the pump inside the tank. There was just too much hardware and it looked ugly. Not only that, but my female Eastern Newt hated being in the water when the pump was on (the male was fine with it). So that being the case, I went looking for alternatives.

I tried hooking up the canister filter to the chiller, but there was not enough flow and the chiller was running way too often (every few minutes). I think a lower GPH rated chiller would have been fine with this, but mine has a supposed minimum rating of 633 GPH.

Luckily my EcoPlus Submersible pump can also be used as an external inline pump.
I tested it out in my bathtub for a few hours to make sure it wasn't going to leak, then installed it with my canister filter. The order of hardware goes like this:

Tank (intake) > Canister Filter > Pump > Ball Valve > Chiller > Tank (Spraybar)

To get this to work, I removed the impeller from the canister filter and left it off. The EcoPlus pump runs the whole thing. So far everything has worked out with the valve all the way open. There's probably a good 10 feet of tubing the pump has to push up through and it's pulling through the filter, so that probably reduced the flow quite a bit.

My canister filter is an old Rena Filstar XP2, and is rated at 300 GPH (before filtration). The largest version of this filter runs at 450 GPH and uses the same gasket and clips that mine uses, so I figured there was a good chance this would be safe and not start pulling gunk from my filter into the tank.

Everything works great! today I'm running the tank at 66°F / 18.9°C and it is not working very hard to maintain this temp in a 74°F / 23.3°C environment.

I also benefit from having some extra power running the canister. Most importantly, my newts are happy and not trying to climb out of the tank.