During the winter the water gets rather cold and I'm considering one of two solutions - either pumping the water into a 400 gallon tank so it can reach room temp or running it through a tankless water heater to heat it to 78. Is this a safe thing to do or is there a good reason to not run the water via tankless water heater ?
Can a tankless water heater be used for warming cold water during hte winter ?
- Thread starter jake37
- Start date
I assume you are talking about the new water you are using for water changes? If yes, I have used both methods you mention.
I have a number of large water storage tanks in the insulated crawlspace under half of my house, which allow water to warm up to ambient temperatures for a change. An airline in each tank keeps the water temperature even throughout, and water feeds by gravity to the aquariums. Some of the storage bins have heaters in them to provide water at warmer temperatures for tanks that require that.
This method works really well, but in my case I didn't have the storage capacity to do all my water changes all on the same day. I reasoned that a tankless system was the answer, so recently installed one. It's finicky to get it just right; various models require various flow rates to operate properly, and all are designed to produce hot water for washing, etc. To get one to provide you with water temperatures at a usable level for fish tanks takes a lot of trial and error. I'll be honest; I'm a dyed-in-the-wool DIY-er but I was totally at sea with this thing; fortunately a good friend who is an industrial plumber helped me out and even he was a bit puzzled by the project. We got it all hooked up and running eventually, but it took multiple trips into town and multiple internet orders to get everything set up, with lots of dead ends and false starts.
Now it's up and running, and it does what it is supposed to do; supply a continuous supply of water at a certain temperature...although getting it to supply that particular temperature was a horror show. And I'm still not completely in love with it, simply because it provides only that one temperature, in my case 72F. I have a couple tanks that I prefer a bit warmer, so I still store water and pre-heat it for them. And I have several that require cooler water, at least at some seasons, so the water for them still needs to be stored to ambience.
The remainder of my tanks are just fine at 72F, so I can now do all my water changes on the same day, but it isn't the seamless process I had envisioned. After all the jumping through hoops to get a consistent 72F, I wouldn't dream of trying to alter it even a few degrees and risk losing my place and starting all over again.
So your choice would be influenced by several factors: willingness and ability to do the plumbing, amount of space you have available for storage bins, cost considerations of the installation (tankless heater + plumbing + pressure balancing valve + electrical work + incidentals will likely cost far more than a few storage bins), etc.
I'd say that if you have the room for the storage tanks, and if the ambient temperature where you store them is close enough to the desired aquarium temperature, that this method is preferable. If, on the other hand, you are considering switching your entire house over to a high-capacity tankless system, then doing the extra work of plumbing hot/cold water lines to your fishroom and installing a pressure-balancing valve might be preferable. I would never suggest that someone go the route that I did, i.e. get a small tankless unit and devote it to supply water strictly for aquarium use.
I have a number of large water storage tanks in the insulated crawlspace under half of my house, which allow water to warm up to ambient temperatures for a change. An airline in each tank keeps the water temperature even throughout, and water feeds by gravity to the aquariums. Some of the storage bins have heaters in them to provide water at warmer temperatures for tanks that require that.
This method works really well, but in my case I didn't have the storage capacity to do all my water changes all on the same day. I reasoned that a tankless system was the answer, so recently installed one. It's finicky to get it just right; various models require various flow rates to operate properly, and all are designed to produce hot water for washing, etc. To get one to provide you with water temperatures at a usable level for fish tanks takes a lot of trial and error. I'll be honest; I'm a dyed-in-the-wool DIY-er but I was totally at sea with this thing; fortunately a good friend who is an industrial plumber helped me out and even he was a bit puzzled by the project. We got it all hooked up and running eventually, but it took multiple trips into town and multiple internet orders to get everything set up, with lots of dead ends and false starts.
Now it's up and running, and it does what it is supposed to do; supply a continuous supply of water at a certain temperature...although getting it to supply that particular temperature was a horror show. And I'm still not completely in love with it, simply because it provides only that one temperature, in my case 72F. I have a couple tanks that I prefer a bit warmer, so I still store water and pre-heat it for them. And I have several that require cooler water, at least at some seasons, so the water for them still needs to be stored to ambience.
The remainder of my tanks are just fine at 72F, so I can now do all my water changes on the same day, but it isn't the seamless process I had envisioned. After all the jumping through hoops to get a consistent 72F, I wouldn't dream of trying to alter it even a few degrees and risk losing my place and starting all over again.
So your choice would be influenced by several factors: willingness and ability to do the plumbing, amount of space you have available for storage bins, cost considerations of the installation (tankless heater + plumbing + pressure balancing valve + electrical work + incidentals will likely cost far more than a few storage bins), etc.
I'd say that if you have the room for the storage tanks, and if the ambient temperature where you store them is close enough to the desired aquarium temperature, that this method is preferable. If, on the other hand, you are considering switching your entire house over to a high-capacity tankless system, then doing the extra work of plumbing hot/cold water lines to your fishroom and installing a pressure-balancing valve might be preferable. I would never suggest that someone go the route that I did, i.e. get a small tankless unit and devote it to supply water strictly for aquarium use.
This is actually a new house so i can do it either way - also my target temp is 78 which is probably a bit easier than 72. However I can do it either way. I wouldn't put an air tube in the bin - but i would like some kind of delay float system so the tank doesn't immediately refill (this is if i don't use the tankless water heater). The tanks would be around 400 gallons - there would be two one for ro and one for filtered water. The large tanks would use a drip system (approx 1-2 gph); the smaller tanks would be manually changed (large is ~400 gallon small is ~120 or smaller).
However it sounds like you strongly suggest skipping the tankless water heater and just using a 400 gallon storage bin. The biggest problem I have with the storage bins is finding some sort of delay float switch so the storage tank doesn't refill until after a period of time. I.e, use some water - wait an hour (so other changes can be done) and then refill completely). This would work as long as i don't use all the water and compelete all water changes in configured duration.
-
I'm not worried about putting cold water into the large tanks (if the water change uses most of the water) since it is a small amount of water over a long period of time.
-
However it sounds like you strongly suggest skipping the tankless water heater and just using a 400 gallon storage bin. The biggest problem I have with the storage bins is finding some sort of delay float switch so the storage tank doesn't refill until after a period of time. I.e, use some water - wait an hour (so other changes can be done) and then refill completely). This would work as long as i don't use all the water and compelete all water changes in configured duration.
-
I'm not worried about putting cold water into the large tanks (if the water change uses most of the water) since it is a small amount of water over a long period of time.
-
Yeah, not sure what I can say that would be of use here. I have the storage tanks permanently plumbed to fill from the cold water lines and to drain into the various aquariums...but all this is controlled by me, manually opening and closing assorted valves. I typically empty most or all of the bins each time I do a change; then I re-fill them immediately to let them sit and warm up for the next one.
Your system sounds like mine was...insofar as requiring a bunch of trial-and-error, profanity, patience and periods of questioning one's own sanity...
. You'll get it right, and it will be worth it.Good luck, keep us posted!
Edited to add: without an airline in the storage bins, and with a slow drip-type fill, I would suspect that you will get a lot of temperature stratification, and if you are feeding the aquariums by gravity, you will be drawing from the bottom, i.e. the coldest water in the tank. Aeration will prevent that; I like being able to check the temperature on all the storage bins and all my aquariums with a laser thermometer, and knowing that each container is consistent top to bottom.
Last edited:
Well one part that will be easier (than yours I think) is i view it being filter system/ro system -> storage tank -> well pump -> pipes - so all i have to do is open the valves by the aquarium and the water flow into the tank. The only part that i think is difficulit is finding the right kind of float switch to shut off ro/filter when the storage bin is full. I only tink I need the delay on the filter system since the ro system itself is slow. The filter system is just one of those large carbon tubes that remove chlorine so it should run at valve flow rate.Yeah, not sure what I can say that would be of use here. I have the storage tanks permanently plumbed to fill from the cold water lines and to drain into the various aquariums...but all this is controlled by me, manually opening and closing assorted valves. I typically empty most or all of the bins each time I do a change; then I re-fill them immediately to let them sit and warm up for the next one.
Your system sounds like mine was...insofar as requiring a bunch of trial-and-error, profanity, patience and periods of questioning one's own sanity...
Good luck, keep us posted!
I am so accustomed to non-chlorinated, non-treated well water...that I tend to forget it's a concern for many aquarists!
See my added comment regarding aeration in my previous post; I edited it, likely after you read it. I think that aeration and water movement in the storage bins is extremely important.
See my added comment regarding aeration in my previous post; I edited it, likely after you read it. I think that aeration and water movement in the storage bins is extremely important.
I don't quite understand; are you saying if the room is 78 degree the water in the tank will stay cold unless i circulate it? Also there will be slight movement since i will be drawing approx 3 gph continously from the storage bin (2 400 gallon aquariums). I guess I could insert an airtube if needed.I am so accustomed to non-chlorinated, non-treated well water...that I tend to forget it's a concern for many aquarists!
See my added comment regarding aeration in my previous post; I edited it, likely after you read it. I think that aeration and water movement in the storage bins is extremely important.
The room with the storage bins is below ground so keeping at 78 shouldn't be too expensive. The room above it has the large aquariums and hte room adjacent will have additional aquariums.
Oh yea i will be on city water so chlorine - at least my city still use chlorine.... which i suppose is a bonus.
Maybe I'm misunderstanding; it sounds like the bin will be drip-filled from a cold water line. In that case, you will see a difference of up to 5 or 6 degrees between the top and bottom of the bin, depending largely upon the depth of the water in there...and you will be drawing from the coldest part of that range.
I didn't use the airline either until the laser thermometer showed me that I practically had a thermocline right in my basement!
A simple bubbler...didn't even bother with an airstone, as they clog up fairly quickly...solved that issue.No - i realize my description above was confusing. The 2 400 gallon aquariums will be drip filled from the storage bins. The 400 gallon storage bins will be filled at ro and filter water system speed. The ro unit will not be super fast but the filter system should be fairly fast. The bulk of the 400 gallon storage bin will sit fill. A bit of water will used for the drip system to the 400 gallon aquariums but that will be a small amount of water relative to the volume at room temp and as it sinks (colder water should sink) it should quickly reach room temp. During water change a large amount of water will be used - probably 200 to 300 gallons. But if the float switch has a delay then it should be rapidly filled after water changes and then allowed to reach room temp before the next water change (that is the idea who knows if it will work). Yes some cold water will be used to the drip system for the 400 gallon aquariums but that shouldn't matter since it is a small amount of water being injected into the aquarium.
Maybe I'm misunderstanding; it sounds like the bin will be drip-filled from a cold water line. In that case, you will see a difference of up to 5 or 6 degrees between the top and bottom of the bin, depending largely upon the depth of the water in there...and you will be drawing from the coldest part of that range.
I didn't use the airline either until the laser thermometer showed me that I practically had a thermocline right in my basement!
Okay, yes, I was misunderstanding where the drip was dripping.
Easy enough to check after you get everything set up. If you have no problem...you have no problem! If you do find that the bottom remains too cold (and I kinda sorta think it will...) it will be easy enough to drop in an airline later. Do you have a central air supply system?
Easy enough to check after you get everything set up. If you have no problem...you have no problem! If you do find that the bottom remains too cold (and I kinda sorta think it will...) it will be easy enough to drop in an airline later. Do you have a central air supply system?