BradB
Well-Known Member
3 years ago, I bought Tropic Marin's "High Precision Hydrometer". I've been the hobby over 20 years and had 2 refractometers, a cheap hydrometer and salinity probe previously. I didn't throw those away, but haven't used them and might need a while to look for them. I thought this hydrometer was really great and gave me easy, quick and accurate readings compared to anything previously, and kept my tank around 1.026.
Yesterday at 1:30pm, I finally got around to a long overdue 70 gallon water change in my 270 display. I've done this a lot, so I normally add most of the salt, then measure to see where I am at, repeatedly measure and add salt until I am at 1.026. I also drain the sump while I am doing that to save time. On my first measurement, I was way over the highest the hydrometer could measure. My mind was on other things, so I can't rule out adding an extra bag of Instant Ocean by mistake, but I've never done that before. I assumed I'd just run the RO until my salinity dropped, and took another 10 gallons (eventually 40 gallons as I repeated this) out of the system to approximate what I was over. My RO is rated 150 gpd, so I assumed this was a 2-3 hour mistake.
Since my reservoir only holds 75 gallons, I drained 5 gallons into a 30 gallon rubbermaid and ran the RO into that until it measured 1.026 and added it to the sump. This took a lot longer than I thought. I then ran the RO straight into the reservoir to replace those 5 gallons and repeated the process. At midnight, I had enough in my sump to start my return pump, but not to run it continuously! I could tell the reservoir salinity was dropping, but it was still above 1.030. I realized my RO is not giving me 150gph, probably a little less than 100gph. I went to bed and ran the RO to an empty rubbermaid.
At 6am, I first manually bailed the rubbermaid RO water into my reservoir, thinking it would be enough to lower the salinity to 1.026. It was not. Thankfully I left 5 gallons of water which I was able to make 1.026 of water. My return still wouldn't run constantly, but I had another 90 minutes before I had to leave so I left the RO running into the empty rubbermaid and had coffee. Another hour probably would have been enough to leave the return running when I left the house.
After another hour, I added 5 gallons from the reservoir to the rubbermaid and took my first measurement. The hydrometer didn't even drop enough to hit the scale! I immediately noticed the bottom cracked and broke off and all the lead (or whatever else) came out. I discarded the water, broken glass and whatever else was in my test beaker, but can't figure out how the hydrometer broke. I had to leave, but left the RO running into an empty rubbermaid and bought a $10 hydrometer before I got home at noon.
The new hydrometer shows my tank water at 1.030! The reservoir water is even higher. I mixed 1.025 water with my reservoir and the rubbermaid, which was enough to run the return continuously. I am running the RO straight into the system, which is about as fast as I dare to lower my salinity, and hopefully raise my water level to the point I am comfortable leaving the house again at 5pm.
So what happened? Was the hydrometer broken before this morning? If it had a hairline crack, would water have gotten in and given me a low reading? How does it break high without the ball bearings coming out? How is my system so high salinity? How did I get so much salinity in my reservoir? Could the new hydrometer be inaccurate? Should I buy another "High Precision Hydrometer"? I like manual devices over electronic or optic, especially as a backup, as I don't have to worry about calibration. Using a refractometer as my primary with a hydrometer as a backup is fine, but not the other way around.
Yesterday at 1:30pm, I finally got around to a long overdue 70 gallon water change in my 270 display. I've done this a lot, so I normally add most of the salt, then measure to see where I am at, repeatedly measure and add salt until I am at 1.026. I also drain the sump while I am doing that to save time. On my first measurement, I was way over the highest the hydrometer could measure. My mind was on other things, so I can't rule out adding an extra bag of Instant Ocean by mistake, but I've never done that before. I assumed I'd just run the RO until my salinity dropped, and took another 10 gallons (eventually 40 gallons as I repeated this) out of the system to approximate what I was over. My RO is rated 150 gpd, so I assumed this was a 2-3 hour mistake.
Since my reservoir only holds 75 gallons, I drained 5 gallons into a 30 gallon rubbermaid and ran the RO into that until it measured 1.026 and added it to the sump. This took a lot longer than I thought. I then ran the RO straight into the reservoir to replace those 5 gallons and repeated the process. At midnight, I had enough in my sump to start my return pump, but not to run it continuously! I could tell the reservoir salinity was dropping, but it was still above 1.030. I realized my RO is not giving me 150gph, probably a little less than 100gph. I went to bed and ran the RO to an empty rubbermaid.
At 6am, I first manually bailed the rubbermaid RO water into my reservoir, thinking it would be enough to lower the salinity to 1.026. It was not. Thankfully I left 5 gallons of water which I was able to make 1.026 of water. My return still wouldn't run constantly, but I had another 90 minutes before I had to leave so I left the RO running into the empty rubbermaid and had coffee. Another hour probably would have been enough to leave the return running when I left the house.
After another hour, I added 5 gallons from the reservoir to the rubbermaid and took my first measurement. The hydrometer didn't even drop enough to hit the scale! I immediately noticed the bottom cracked and broke off and all the lead (or whatever else) came out. I discarded the water, broken glass and whatever else was in my test beaker, but can't figure out how the hydrometer broke. I had to leave, but left the RO running into an empty rubbermaid and bought a $10 hydrometer before I got home at noon.
The new hydrometer shows my tank water at 1.030! The reservoir water is even higher. I mixed 1.025 water with my reservoir and the rubbermaid, which was enough to run the return continuously. I am running the RO straight into the system, which is about as fast as I dare to lower my salinity, and hopefully raise my water level to the point I am comfortable leaving the house again at 5pm.
So what happened? Was the hydrometer broken before this morning? If it had a hairline crack, would water have gotten in and given me a low reading? How does it break high without the ball bearings coming out? How is my system so high salinity? How did I get so much salinity in my reservoir? Could the new hydrometer be inaccurate? Should I buy another "High Precision Hydrometer"? I like manual devices over electronic or optic, especially as a backup, as I don't have to worry about calibration. Using a refractometer as my primary with a hydrometer as a backup is fine, but not the other way around.
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