I fill a 55 gallon water barrel while draining and have a pump running to circulate the Prime that I throw in. Sometimes I had to wait while the water was heated up to where I need it but with the thermometer, I no longer have to wait. Once it's drained down to the line, I can immediately pump it in. Is what I made an extra and unnecessary step? Yes but it makes it easier on me and that was my whole intention.
Matching temperature during water changes
- Thread starter lil_pendejo
- Start date
I use a separate food grade 1000ltr IBC that I fill 2 days before, de-chlorinate, add my salt and KH (I have very soft water) and run a 500w heater and air stone. Test before I add using a pump. Take 10mins to do a 800ltr water change.
That's the exact plan that I have for the fishroom I'm building in my garage but I'm planning on a 375 gallon IBC.
If you get straight from the tap and de chlorinate afterwards does that risk a bacterial die off?
Just make sure it’s new food grade. Often the second hand ones will have been used to store chemicals even pesticides before.
I live in a somewhat rural area and our water suppy isn't the best. I don't trust it to the point that I would add water straight to the tank and then dechlorinate even if the temp matches. I run the water through 2 carbon blocks and then dechlorinate with Prime once in the 55 gallon and the pump is running. Ihad issues with a 16 gallon cube when I first bought this house and haven't trusted it since.
Finding a new food grade is a problem by me. I have no desire to drive 3 hours one way to pick it up and shipping is ridiculous so I'm still hunting for one locally.
My reading says the charcoal will take care of chlorine and chloramine. I ended up buying an RO filter (for soft water for the discus tank), and the 2nd and 3rd stages are charcoal. Then I got two 50 gallon rain barrels. One holds the RO water, and the other gets the “waste” water, which I use for Central American cichlid tanks. The waste water has been through the particle filter and both charcoal filters, and has mildly higher mineral levels than the tap water—perfect! The barrels have heaters in them, so the water is ready to pump right into the tanks.
My question is about thermometers—the readings are so variable I am not sure which to believe. How do you evaluate your different tank thermometers??
If you want to evaluate them in terms of how accurate they are...beats me! Back in the day when I used the cheapo glass thermometers with the red solution in the tube...meaning right up until today, because I still have a dozen or so floating around 
...I would just check out every thermometer on the shelf in the store. If 10 of them say 78F, one says 80F and one says 75F, I would just make sure not to buy one of the outliers. Very scientific, huh?
I now use a laser thermometer, which you'd think would be 100% accurate all the time...but I think you'd be wrong. Aside from the differing emissivity of different materials, you must remember that you are measuring the temperature of the outside of the container. A larger tank made of thicker material reads differently than one made of thinner glass, and the difference becomes even more noticeable in a room where the air temperature is variable. And of course glass, acrylic and wood will all read differently as well. To minimize these variables, I try to take readings by pointing the laser down into the water from above, with no lids on. I think that is likely the most accurate actual reading, but of course much of the convenience of using the laser is then lost if you have to open the top of each tank each time.
A bit of experience with your individual tanks is useful. I know that a 360 plywood, a 120 plywood and a 75 all-glass will all read differently, even when the water (as tested with another thermometer moved from tank to tank) is exactly the same temperature. If I adjust the laser for differing emissivities, I can get all the tanks to read the same...fat chance I'm gonna bother with that! I'm only looking for comparative values from one day to the next.
I want to step in the door, laser all the tanks quickly and be done. My storage tanks are tucked up in the crawlspace adjoining my basement, so it's great just to dance the red dot around on them and get quick'n'dirty readings. I rarely...in fact, likely never...care if the temperature is 75.2 as opposed to 76.5, that much of a difference is meaningless to me. If I get within a couple of degrees, that's good enough.
It's especially interesting to laser the outside of my outdoor stock tanks in warm weather. They are completely stagnant and unaerated, no water circulation at all, and taking readings at several levels is an eye-opener. There can easily be 5 or 10 Fahrenheit degrees difference between the very bottom and the top; if you then take a reading down through the water, you get another reading still. The clearer the water, the more accurately you can read the temp of a stone, piece of wood, plant leaf or the bottom; if the water is at all turbid, you get a reading very close to that of the surface water itself.
If you actually want/need an accurate reading, I think you need to go with a digital readout thermometer that has a remote probe, as long as you are careful not to place the probe too close to the heater, and also ensure that there is good water circulation in your tank. Several of these will still be cheaper than a single laser, and they work very well for reading a few tanks.
...I would just check out every thermometer on the shelf in the store. If 10 of them say 78F, one says 80F and one says 75F, I would just make sure not to buy one of the outliers. Very scientific, huh?I now use a laser thermometer, which you'd think would be 100% accurate all the time...but I think you'd be wrong. Aside from the differing emissivity of different materials, you must remember that you are measuring the temperature of the outside of the container. A larger tank made of thicker material reads differently than one made of thinner glass, and the difference becomes even more noticeable in a room where the air temperature is variable. And of course glass, acrylic and wood will all read differently as well. To minimize these variables, I try to take readings by pointing the laser down into the water from above, with no lids on. I think that is likely the most accurate actual reading, but of course much of the convenience of using the laser is then lost if you have to open the top of each tank each time.
A bit of experience with your individual tanks is useful. I know that a 360 plywood, a 120 plywood and a 75 all-glass will all read differently, even when the water (as tested with another thermometer moved from tank to tank) is exactly the same temperature. If I adjust the laser for differing emissivities, I can get all the tanks to read the same...fat chance I'm gonna bother with that! I'm only looking for comparative values from one day to the next.
I want to step in the door, laser all the tanks quickly and be done. My storage tanks are tucked up in the crawlspace adjoining my basement, so it's great just to dance the red dot around on them and get quick'n'dirty readings. I rarely...in fact, likely never...care if the temperature is 75.2 as opposed to 76.5, that much of a difference is meaningless to me. If I get within a couple of degrees, that's good enough.
It's especially interesting to laser the outside of my outdoor stock tanks in warm weather. They are completely stagnant and unaerated, no water circulation at all, and taking readings at several levels is an eye-opener. There can easily be 5 or 10 Fahrenheit degrees difference between the very bottom and the top; if you then take a reading down through the water, you get another reading still. The clearer the water, the more accurately you can read the temp of a stone, piece of wood, plant leaf or the bottom; if the water is at all turbid, you get a reading very close to that of the surface water itself.
If you actually want/need an accurate reading, I think you need to go with a digital readout thermometer that has a remote probe, as long as you are careful not to place the probe too close to the heater, and also ensure that there is good water circulation in your tank.
Several of these will still be cheaper than a single laser, and they work very well for reading a few tanks.
John—If you want to evaluate them in terms of how accurate they are...beats me! Back in the day when I used the cheapo glass thermometers with the red solution in the tube...meaning right up until today, because I still have a dozen or so floating around
I now use a laser thermometer, which you'd think would be 100% accurate all the time...but I think you'd be wrong. Aside from the differing emissivity of different materials, you must remember that you are measuring the temperature of the outside of the container. A larger tank made of thicker material reads differently than one made of thinner glass, and the difference becomes even more noticeable in a room where the air temperature is variable. And of course glass, acrylic and wood will all read differently as well. To minimize these variables, I try to take readings by pointing the laser down into the water from above, with no lids on. I think that is likely the most accurate actual reading, but of course much of the convenience of using the laser is then lost if you have to open the top of each tank each time.
A bit of experience with your individual tanks is useful. I know that a 360 plywood, a 120 plywood and a 75 all-glass will all read differently, even when the water (as tested with another thermometer moved from tank to tank) is exactly the same temperature. If I adjust the laser for differing emissivities, I can get all the tanks to read the same...fat chance I'm gonna bother with that! I'm only looking for comparative values from one day to the next.
I want to step in the door, laser all the tanks quickly and be done. My storage tanks are tucked up in the crawlspace adjoining my basement, so it's great just to dance the red dot around on them and get quick'n'dirty readings. I rarely...in fact, likely never...care if the temperature is 75.2 as opposed to 76.5, that much of a difference is meaningless to me. If I get within a couple of degrees, that's good enough.
It's especially interesting to laser the outside of my outdoor stock tanks in warm weather. They are completely stagnant and unaerated, no water circulation at all, and taking readings at several levels is an eye-opener. There can easily be 5 or 10 Fahrenheit degrees difference between the very bottom and the top; if you then take a reading down through the water, you get another reading still. The clearer the water, the more accurately you can read the temp of a stone, piece of wood, plant leaf or the bottom; if the water is at all turbid, you get a reading very close to that of the surface water itself.
If you actually want/need an accurate reading, I think you need to go with a digital readout thermometer that has a remote probe, as long as you are careful not to place the probe too close to the heater, and also ensure that there is good water circulation in your tank.
You make some very good points. I agree that precision is not too important. I like the quick check idea—I have been using a $7 meat thermometer, which needs a water dip for a few seconds, alongside a bunch of digital thermometers with probe in the tank and readout on the outside. But those are a bit unsightly. Your stock tanks exemplify the pond temp differences that prove sudden temp changes will probably not hurt the fish. My question stems from a frustration with uncertainty about whether my choice of tank temperature will be where it ends up. Or how close…
