Painting vs Re-Plastering
- Thread starter JPMorgan
- Start date
Our pool company says they recommend an annual drain and clean (probably because most pools are using bromine or chlorine tabs for sanitizer), but it sounds like this wouldn't really be necessary if we switch to sodium bromide / liquid chlorine to sanitize our indoor pool, correct? If we did that, how long could we extend the time between water changes?
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One more question.... when you have higher CYA levels in a pool you keep FC at a higher level. Until we get the pool drained and refilled should I maintain the bromine in the pool at a higher level.... say 10 ppm instead of 4 ppm?
As close to the allowed limit as possible.
Hard to say.
What is the current salinity as measured by a K-1766 salt test kit and as measured by a conductivity meter set to NaCl (Salt)?
Don't have either of those, so I'll have to get them. Are both necessary? Will the salinity level determine when to change the water in the pool? If so, at what level?
Products like DMH can be calculated from the amount of tabs used.
Disinfection byproducts can accumulate over time.
DBPs (Disinfection byproducts) are hard to measure unless you have a lab that is qualified to test for these things.
TDS can give you some indication of DBP accumulation over time.
If you compare the salinity as measured by a conductivity meter and subtract the salinity as measured by a K-1766 salt test kit, the difference can indicate problems.
The bigger the difference, the more non-salt compounds are in the water.
For a commercial pool, you want to dilute based on the usage as various types of organic and inorganic molecules can accumulate.
The DIN Standard (used in German public pool operation and in many other European countries), it is a formula for replacement of water daily.
The formula is based on the number of bathers per day.
Formula: Replace 7.9 gallons of water for each bather each day.
UV can be helpful in addressing water quality issues in an indoor commercial pool.
Testing for combined bromine can be useful even though most sources say that you will never get combined readings.
Bromine pools will get substantially more combined readings than most chlorine pools due to various types of brominated compounds.
Improved DBP elimination from swimming pool water by continuous combined UV and ozone treatment - PubMed
Chlorine is the most frequently used disinfectant and oxidant for maintaining swimming pool water quality; however, it reacts continuously with dissolved organic matter to produce disinfection by-products (DBPs), which are a health risk for pool users. UV treatment is used widely to remove...
pubmed.ncbi.nlm.nih.gov
Disinfection Byproducts in Chlorinated or Brominated Swimming Pools and Spas: Role of Brominated DBPs and Association with Mutagenicity - PMC
Although the health benefits of swimming are well-documented, health effects such as asthma and bladder cancer are linked to disinfection by-products (DBPs) in pool water. DBPs are formed from the reaction of disinfectants such as chlorine (Cl) or ...
www.ncbi.nlm.nih.gov
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Sure seems like sanitizing with chlorine and CYA is a lot easier.Products like DMH can be calculated from the amount of tabs used.
Disinfection byproducts can accumulate over time.
DPBs (Disinfection byproducts) are hard to measure unless you have a lab that is qualified to test for these things.
TDS can give you some indication of DPB accumulation over time.
If you compare the salinity as measured by a conductivity meter and subtract the salinity as measured by a K-1766 salt test kit, the difference can indicate problems.
The bigger the difference, the more non-salt compounds are in the water.
For a commercial pool, you want to dilute based on the usage as various types of organic and inorganic molecules can accumulate.
The DIN Standard (used in German public pool operation and in many other European countries), it is a formula for replacement of water daily.
The formula is based on the number of bathers per day.
Formula: Replace 7.9 gallons of water for each bather each day.
UV can be helpful in addressing water quality issues in an indoor commercial pool.
Testing for combined bromine can be useful even though most sources say that you will never get combined readings.
Bromine pools will get substantially more combined readings than most chlorine pools due to various types of brominated compounds.
Improved DBP elimination from swimming pool water by continuous combined UV and ozone treatment - PubMed
Chlorine is the most frequently used disinfectant and oxidant for maintaining swimming pool water quality; however, it reacts continuously with dissolved organic matter to produce disinfection by-products (DBPs), which are a health risk for pool users. UV treatment is used widely to remove...Disinfection Byproducts in Chlorinated or Brominated Swimming Pools and Spas: Role of Brominated DBPs and Association with Mutagenicity - PMC
Although the health benefits of swimming are well-documented, health effects such as asthma and bladder cancer are linked to disinfection by-products (DBPs) in pool water. DBPs are formed from the reaction of disinfectants such as chlorine (Cl) or ...
This is an indoor pool. My understanding is that bromine is a better option for an indoor pool. I would appreciate any comments on that vs. just using liquid chlorine as a sanitizer. What I found out today is that the HOA had a practice of draining, cleaning and refilling the indoor pool every year. This cost about $2,000 (for the service and the fill water.) This makes sense as long as we are using bromine tablets because of the build-up of DMH. I'm trying to figure out if it would be more cost effective to use sodium bromide and liquid chlorine. There is some cost involved to add the equipment to accomplish this (a pump and some tubing... we already have a liquid chlorine tank). The key factor is how long this will extend the "life" of the water in the pool if we use this method.Sure seems like sanitizing with chlorine and CYA is a lot easier.
So... I'm looking for a ballpark figure without getting too complicated. Could we go 2 years.... 3 years.... or longer... between drain and re-fills if we used sodium bromide and liquid chlorine and eliminated the tablets? Would it makes just as much sense to forget about using sodium bromide in the pool and just use liquid chlorine with a little bit of stabilizer. I'm assuming we wouldn't need much since this is an indoor pool. It does get sun through a bank of large windows on one side of the pool, but that's not the same as direct sunlight, is it?
You can get DBPs from a chlorine pool as well.
A high use indoor commercial pool is very difficult to keep properly sanitized without making the water and air intolerable.
Most commercial pools are not operated at peak water quality.
I would use liquid chlorine and CYA if you are allowed to use CYA.
You should be diluting the water based on person hours.
1 Person-Hour is 1 person for 1 hour.
Replace 8 gallons per person hour every day to keep the water fresh.
Maybe switch to SWG when the salinity from liquid builds up to 1,600 ppm.
Maybe just go straight to SWG and add 1,600 ppm salt.
A Hayward Aquarite with a T-15 cell set to T-9 or T-5 will allow you to use 1,600 ppm salt with good results.
1,600 ppm salt with a T-15 cell but set to T-5 will read as 3,200 ppm salt.
I would use a UV System on an Indoor Commercial Pool.
You should be diluting the water based on person hours.
1 Person-Hour is 1 person for 1 hour.
Replace 8 gallons per person hour every day to keep the water fresh.
Maybe switch to SWG when the salinity from liquid builds up to 1,600 ppm.
Maybe just go straight to SWG and add 1,600 ppm salt.
A Hayward Aquarite with a T-15 cell set to T-9 or T-5 will allow you to use 1,600 ppm salt with good results.
1,600 ppm salt with a T-15 cell but set to T-5 will read as 3,200 ppm salt.
I would use a UV System on an Indoor Commercial Pool.
Aquarite Cell Plates.
Here are the dimensions of the Hayward plates:T-15 has 13 Titanium Plates, 150 x 63mm. Produces 1.47 lbs/day.
T-9 has 13 Titanium Plates, 101 x 63mm. Produces 0.98 lbs/day.
T-5 has 7 Titanium plate, 150 x 63mm. Produces 0.735 lbs/day.
T-3 has 7 Titanium Plates, 101 x 63mm. Produces 0.53 lbs/day.
Hayward plates come from DeNora which is an Italian company.[15]
I wouldn't call our pool "high use". A few regulars... maybe 3-4 swimmers daily (if that) and the occasional gps with the gks. The pool is probably unoccupied 90% of the time. I don't think there is any issue with keeping it properly sanitized, especially with the Controller and bromine and acid feeders we use. I'm just trying to figure out if eliminating the bromine tablets and using sodium bromide/ liquid chlorine.... or just straight liquid chlorine would extend the "life" of the water and be a more cost effective approach than draining and re-filling the pool each year. I'm really looking for some plain and simple information that I could share with our HOA to help determine if we just stick with the current system or change the way we sanitize the pool and get additional "life" out of the water. Anything too complicated and their eyers will glaze over. I don't think we want to switch to UV or SWG systems. Right now we have a chlorine feeder and a bromine feeder. Only the bromine feeder is used at this time. Is there any gain to switching to sodium bromide/ liquid chlorine or straight liquid chlorine in terms of extending the "life of the water and reducing the frequency of refills?
It will definitely help.
I would not use bromine tabs for any pool.
Tabs are probably ok up to about 40 ppm DMH and then no more.
If you can regularly dilute with fresh water, you can probably go indefinitely without ever needing to drain and refill.
The salinity reading can help you determine if you are diluting enough.
Before backwashing, add as much water as possible to the pool and then do a Backwash, Rinse and then Waste until the water level is correct.
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The regular outdoor chlorine pools don’t ever need to be completely drained if they are managed well. Not sure about the difference for indoor pools though. Someone in another post mentioned something about bromine exposure being problematic in some cases, but I don’t know the details. That’s enough for me to not want to swim in one.
So… if we drain and clean the pool this winter which alternate method do you think would be better in order to eliminate annual draining and cleaning… adding sodium bromide and using the liquid chlorine feeder or just using liquid chlorine as our sanitizer? If we use only use the liquid chlorine how much, if any, stabilizer should be in the pool? Remember, it is an indoor pool that gets some sunlight through a bank of windows along one side of the pool.
I would use liquid chlorine plus about 30 ppm CYA if it is allowed.
I would also use UV.
Without UV, you might be better off using sodium bromide and liquid chlorine.
Start with liquid chlorine and you can always add sodium bromide if you want.
I would also use UV.
Without UV, you might be better off using sodium bromide and liquid chlorine.
Start with liquid chlorine and you can always add sodium bromide if you want.
If we go with straight liquid chlorine and maintain 30 ppm CYA, is there any issue of the CYA being in the pool if we decide to add the sodium bromide later? Would we still want to maintain the CYA at 30 with sodium bromide in the pool if we are adding chlorine daily through our automatic feeder?
Bromine does have an equilibrium with CYA like it has with DMH, but I do not know the exact equilibrium constants.
At 30 ppm, the CYA should not interfere with the bromine too much as far as I know.
I would say no, but I do not know for sure if it would help or hurt.
Using about 30 ppm of DMH might be helpful, but I do not know this for certain either.