Heating large tanks with your gas hot water heater. Save 40% on energy cost!

[Dubs83]

Haha, yes, that is right. Even the physically small 55K exchanger is broadly equivalent to 15,000 watts of stick heaters. Means layers of redundancy to avoid overheating.

You clearly missed my point.

 

[ca1ore]

LOL, maybe so since you seemed to be making two different points. That these heat exchangers are made with saltwater pools in mind may translate to longer mean time to failure .... or it may not. That they are ‘sized’ to much higher volumes means being very careful about how you use them to avoid overheating.

 

[User]

I’m using this on a 300 gallon system with zero issues. Spending roughly .20 cents per month on heating costs in northern NJ. I have redundancies in place such as multiple temp probes to remove heat. A fail to closed valve in case of failure. Leak detectors to detect a leak in the event of a heat exchanger leak. I have additional electric heaters in the sump in case this system fails to open. These heaters are individual turned on for 2 min a day so my APEX can determine if they’re still drawing current and give me an alarm when it’s out of range. I run water through the system once every 12 hours to ensure bacteria doesn’t build in the line and affect my drinking water. I feel incredibly confident in this set up and would say it’s a heck of a lot more reliable then electric heaters alone. I look at it from a different perspective and that’s “why would I trust a $30-50 piece of equipment that’s known to fail to protect $3000 worth of live stock”.

One year in this and it’s been flawless

Some very solid points, and the big drawback -contamination of your supply water- is made moot with the circulation code.

To others reading- I’m a PhD level microbiologist. Dubs is being way over cautious with his 12 hour flush cycle. You could do a week and still have safe water. Remember- tap water is chlorinated or otherwise treated and has very few live bacteria in it at the tap. It’s also- usually- pretty nutrient free, so it’s hard to grow bacteria in tap water *even if you literally tried to*

I’m planning to implement this as soon as i finish off some other projects. Set up the way Dubs has it- I trust it way more than I trust an electric heater stick running without a controller. And FWIW- my 2 month old inkbird controller is failing and needs constant compensation of -15of.., which means its reading my 77of water as 92of, and forcin a cooling fan to come in. I lost $100 in my coral QT before I noticed. Point is- even controllers can fail and screw up your day.

The key is multi-redundancy

 

[User]

Haha, yes, that is right. Even the physically small 55K exchanger is broadly equivalent to 15,000 watts of stick heaters. Means layers of redundancy to avoid overheating.

15000 watts of stick heaters can turn your tank into a dry box faster than you think.

Since your water heater temp is set to 125 oF -normally- then your tank isn’t going to get much above that.

Not a comparison that can be made.

I think dubs point was that the titanium heat exchangers have been used in saltwater pools for a long time, and therefore have a proven track record of long term successful use in saltwater.

 

[Dubs83]

LOL, maybe so since you seemed to be making two different points. That these heat exchangers are made with saltwater pools in mind may translate to longer mean time to failure .... or it may not. That they are ‘sized’ to much higher volumes means being very careful about how you use them to avoid overheating.

I pointed out that these heat exchangers are made with pools in mind to highlight that they are built for way more abuse than a typical fish tank hobbyist will every throw at them. Making a leak, in my opinion, highly unlikely.

To your second comment. If you’re not being very careful with whatever equipment you’re using to heat your tank, you will eventually lose your livestock. Suggesting that you shouldn’t be careful about how you use your heaters is generally accepted as “bad advice”

 

[ca1ore]

15000 watts of stick heaters can turn your tank into a dry box faster than you think.

Since your water heater temp is set to 125 oF -normally- then your tank isn’t going to get much above that.

Not a comparison that can be made.

I think dubs point was that the titanium heat exchangers have been used in saltwater pools for a long time, and therefore have a proven track record of long term successful use in saltwater.

Understood, just found the logic a bit muddled. Anyhow, I’ve purchased a heat exchanger from aquarium engineering, though still waiting and waiting for the control board. Probably just should have built it myself. His exchanger seems bigger than most of the pool models folks are using so multiple levels of redundancy will be key to prevent any possibility of runaway heat. I’m also going to use it for cooling.

 

[Dubs83]

Understood, just found the logic a bit muddled. Anyhow, I’ve purchased a heat exchanger from aquarium engineering, though still waiting and waiting for the control board. Probably just should have built it myself. His exchanger seems bigger than most of the pool models folks are using so multiple levels of redundancy will be key to prevent any possibility of runaway heat. I’m also going to use it for cooling.

It’s the same heat exchanger as the OPs, for what it’s worth.

 

[DBR_Reef]

2 year update on this system-

 

[DBR_Reef]

I also have an electric heater on back up and have the apex run it once a day for 5 minutes with power monitoring / alerting set up on that outlet to make sure it actually works.

So as you may see in my 2yr update video- I had my only backup electric heater fail to ground. It could have been bad for 2 years because I never tested it! I just removed all electric heaters. Perhaps I should have done what you did, and have it turn on once a day, but I was worried that if it did fail and I was on vacation, a test turn on would have caused larger problems- are you shutting off the automatic test when you go on vacation?

 

[Blue Carbon Reefing]

great update. this has been working flawlessly for me as well. I will set a reminder to test the back up heaters every fews weeks or so.

 

[Realposition]

Thanks for the update. I checked into getting a heat exchanger but it looks like prices have gone up significantly.

 

[DBR_Reef]

Thanks for the update. I checked into getting a heat exchanger but it looks like prices have gone up significantly.

Yeah, the one off ebay is gone, someone is selling the same thing for $100 more. They can be found elsewhere as well- part number is SP-55Kti-S.

But if you are willing to go with a in sump version there is also this- which is way cheaper.
https://www.fish-street.com/aquarium_titanium_evaporator

There are also titanium shell and tube heat ex changers on aliexpress for under 200 shipped

 

[justingraham]

Why do you guys use a boost pump?
My hot water heater is three feet away from my tank I would think the pressure from that would be fine

 

[Realposition]

Why do you guys use a boost pump?
My hot water heater is three feet away from my tank I would think the pressure from that would be fine

You need something to make the water flow. The pressure on the hot water supply and return are the same.

 

[justingraham]

You need something to make the water flow. The pressure on the hot water supply and return are the same.

So when you turn on the faucet what makes the water come out?

 

[Realposition]

So when you turn on the faucet what makes the water come out?

The pressure inside the pipe being higher than the pressure outside the pipe.

 

[justingraham]

The pressure inside the pipe being higher than the pressure outside the pipe.

So if you return the water back to the same pressurized system no water would circulate is what your saying

 

[Realposition]

So if you return the water back to the same pressurized system no water would circulate is what your saying

Maybe a small amount would circulate or it's possible cold water could push it's way though to the hot side if check valves are not used. To get reliable and adequate hot water flow through the heat exchanger I think a pump would definitely have to be used.

 

[ca1ore]

You could, I suppose, run hot water through the heat exchanger and then to waste. Thus no circulator required. If you ran a slow enough trickle of hot water, perhaps most of the heat would be utilized. Still a waste of water though. Easier, I think to return to the common pressure system and use a small circulator.

 

[Realposition]

Yeah, the one off ebay is gone, someone is selling the same thing for $100 more. They can be found elsewhere as well- part number is SP-55Kti-S.

But if you are willing to go with a in sump version there is also this- which is way cheaper.
https://www.fish-street.com/aquarium_titanium_evaporator

There are also titanium shell and tube heat ex changers on aliexpress for under 200 shipped

Do you know anyone who has used the fish street coil and is confident it's actually fully titanium? I'm nervous it of the quality and if it will leech unwanted metals.