I am looking at using an injection pump to add liquid chlorine daily instead of the 3 inch tabs. I have a 35,000 gallon pool vinyl igp with an auto cover. It seems like I use about 1 lb of tabs per day on average. How much liquid should expect to use daily?
How much liquid chlorine must be added daily?
- Thread starter psuaqua
- Start date
Welcome to TFP.
Proper testing is the only way to know for sure how much to add each day.
We usually figure about 2 to 3 ppm FC loss per day. You can use the pool calc to get a ballpark of how much bleach that it's going to take each day.
Then for the injection pump sizing, take that number and your pump run time and you can figure out what size injection pump you will need.
Proper testing is the only way to know for sure how much to add each day.
We usually figure about 2 to 3 ppm FC loss per day. You can use the pool calc to get a ballpark of how much bleach that it's going to take each day.
Then for the injection pump sizing, take that number and your pump run time and you can figure out what size injection pump you will need.
Before you do anything you need an accurate test kit and you need to make sure that your pool is healthy. If there is any doubt here - then you may need to run an overnight chlorine loss test to make sure you don't have some nasty organics.
In particular you need to know what the Cyanuric acid level is as this will dictate your chlorine level. See here: pool-school/chlorine_cya_chart_shock. Different CYA implies a different chlorine range.
THe amount you use will also depend on the concentration of the chlorine you plan to use. So you'll need to input this data into the pool calculator. pool-school/pool_calculator
In particular you need to know what the Cyanuric acid level is as this will dictate your chlorine level. See here: pool-school/chlorine_cya_chart_shock. Different CYA implies a different chlorine range.
THe amount you use will also depend on the concentration of the chlorine you plan to use. So you'll need to input this data into the pool calculator. pool-school/pool_calculator
Welcome to TFP!
Too many unkowns to answer you properly. It really depends on lots of factors. Cya level, bather load, sun exposure, etc. What else can you tell us?
Too many unkowns to answer you properly. It really depends on lots of factors. Cya level, bather load, sun exposure, etc. What else can you tell us?
Welcome to tfp, psuaqua 
If your pool uses 3 ppm a day as bama suggested for a rough guideline, that would be 108 ounces of 12.5% bleach daily. That is close to your current puck usage (108 ounces of 12.5% bleach is equal to about 15 ounces of trichlor), though depending on what FC you currently maintain and the cya level you have right now, things may change some. Of course you may find that lower percentage bleach is cheaper, so you will want to be able to meter more liquid.
If your pool uses 3 ppm a day as bama suggested for a rough guideline, that would be 108 ounces of 12.5% bleach daily. That is close to your current puck usage (108 ounces of 12.5% bleach is equal to about 15 ounces of trichlor), though depending on what FC you currently maintain and the cya level you have right now, things may change some. Of course you may find that lower percentage bleach is cheaper, so you will want to be able to meter more liquid.
Thanks for the replies. Pool is just used on weekends. CYA is high at 150. I need to get that reduced to a reasonable level. Thus the reason I want to go liquid chlorine or swg, I have no need for stablilizer in tabs, since I have complete control over the rain water to the pool with the auto cover. I just keep building up cya.
At 150 you most likely will need to drain a good amount. I drained over half my pool and got mine down to 40. Managing the pool is easy now.
You can use rains to dilute the water even with the cover on -- just feed the water from the top of the cover into the pool that then overflows to a drain (if that's how yours is set up). That's what I do over the winter, mostly to keep salt levels in check. One has to be a little careful since the pool water can get dirty from what is pumped on the cover, but it's not too bad (at least in my case).
Well at 150 chlorinating will be tough with anything you use. Good thing you are looking at working that down.
Lot's of folks here love the Stenner pumps. I've never used them, but have lot's of experience with a few others. Seems the Stenners do pretty well for pools though.
Lot's of folks here love the Stenner pumps. I've never used them, but have lot's of experience with a few others. Seems the Stenners do pretty well for pools though.
Once you've killed off any nascent algae growth, then maintaining a minimum FC of around 11 ppm with the 150 ppm CYA would probably have a low chlorine usage losing only 15% or so per day so perhaps 1.6 ppm FC per day. The higher CYA level protects chlorine loss from sunlight even with the proportionately higher FC level. The main risk is if you ever have to SLAM the pool -- it will take extraordinary levels of chlorine to do that. This is why we normally say that 80 ppm is a maximum CYA level.
chem geek said:
That was my plan this fall and winter. But will I be diluting the winterizing chemicals too much to render them useless, such as the algacide, oxdixer, shock. The alternative is pumping out half the pool and then having the water truck come in. Rain water is cheaper.
chem geek said:
The CYA was actually higher. I just dumped 25% of the water to get to 150 ppm. I am holding chlorine, turned back my chlorinator. Maybe using 4 lbs. a week. Less than .5 ppm of cc. Free chlorine is at 5ppm. Water is crytal clear.
I have not made transition yet to the BBB method just getting figured out to start the spring right. I have to decide between a swg or a stenner pump system. Either way I am done with tabs.
- May 4, 2011
- 634
If you're still using tabs it won't help much to replace water since the tabs will keep adding more stabilizer. 5ppm is less than half of the FC level you need to maintain at 150ppm CYA.