Dichlor/Bleach in rotomolded tub

[elbow]

Hey All,

I'm a relatively new hot tub owner (3 months). This site has been a super valuable resource for me. I've been using the dichlor/bleach method since the beginning with a ton of success. I've got everything locked in and have had clear water and happy bathers since day one. I have a couple of very quick questions that I haven't really found the answers to on here:

1. I've seen some posts about how bleach could/could not potentially affect acrylic tubs, and it seems that that is what most have. My shell is rotomolded. Just wanted to see if there was anything I should be concerned about with using liquid chlorine on that.

2. I put 50ppm of borates in the tub when I filled. Does anyone ever find that those need to be replenished between fills or does the 50ppm stay pretty steady throughout?

3. I am seeing some bleaching (discoloration) starting to happen on the bottom of my cover already. I keep it off when adding regular chlorine and after soaking for 30-45 minutes and have only hit SLAM levels of chlorine once. I do have an ozonator. Is some bleaching normal or is there something else I should be trying to do to mitigate that?

Thanks again for this resource and the Pool Math app. I'm not really sure where I'd be without them.

Edit: Just saw the new borates post that answered #2.

 

[phonedave]

1. Bleach is just like any other source of chlorine once it is in your water. To be super safe, just pour it into the middle of the tub with the jets or circulator on. Anything you spill on the shell, rinse off.

3. What kind of cover do you have (what material)

 

[Mdragger88]

Hey All,

I'm a relatively new hot tub owner (3 months). This site has been a super valuable resource for me. I've been using the dichlor/bleach method since the beginning with a ton of success. I've got everything locked in and have had clear water and happy bathers since day one. I have a couple of very quick questions that I haven't really found the answers to on here:

1. I've seen some posts about how bleach could/could not potentially affect acrylic tubs, and it seems that that is what most have. My shell is rotomolded. Just wanted to see if there was anything I should be concerned about with using liquid chlorine on that.

It’s fine- just don’t pour it (or any chems) on the shell
I have used this method for 5+ years in my rotomolded tub

2. I put 50ppm of borates in the tub when I filled. Does anyone ever find that those need to be replenished between fills or does the 50ppm stay pretty steady throughout?

I don’t- i do however have a small tub that suffers from a bit of splashout & I generally go at least 6 months between water exchanges/purges so I gradually reduce my borate level in poolmath based on how much water I think I have replaced with fresh so I don’t accidentally overdose with acid.

3. I am seeing some bleaching (discoloration) starting to happen on the bottom of my cover already. I keep it off when adding regular chlorine and after soaking for 30-45 minutes and have only hit SLAM levels of chlorine once. I do have an ozonator. Is some bleaching normal or is there something else I should be trying to do to mitigate that?

The ozonator may certainly be a contributor- especially if it always runs. Its an oxidizer. When it runs out of waste to oxidize it oxidizes other things like your standby fc, head rests, & covers.
If possible, setting it to run just after you usually use the tub is ideal.
Try rinsing & “sunning” the underside of your cover occasionally to keep it supple.

Thanks again for this resource and the Pool Math app. I'm not really sure where I'd be without them.

Edit: Just saw the new borates post that answered #2.

 

[elbow]

1. Bleach is just like any other source of chlorine once it is in your water. To be super safe, just pour it into the middle of the tub with the jets or circulator on. Anything you spill on the shell, rinse off.

3. What kind of cover do you have (what material)

Thanks! It’s from the dealer. The top is like a sunbrella type fabric. The underside which is bleaching a little looks like vinyl.

 

[elbow]

It’s fine- just don’t pour it (or any chems) on the shell
I have used this method for 5+ years in my rotomolded tub

I don’t- i do however have a small tub that suffers from a bit of splashout & I generally go at least 6 months between water exchanges/purges so I gradually reduce my borate level in poolmath based on how much water I think I have replaced with fresh so I don’t accidentally overdose with acid.

The ozonator may certainly be a contributor- especially if it always runs. Its an oxidizer. When it runs out of waste to oxidize it oxidizes other things like your standby fc, head rests, & covers.
If possible, setting it to run just after you usually use the tub is ideal.
Try rinsing & “sunning” the underside of your cover occasionally to keep it supple.

Great! Thank you. Yeah I pour the bleach usually in front of a low jet above a return. Never on the shell.

I have a felling it’s the ozonator. Unfortunately Incant control when it runs. It’s just automatically set up to run when pump 1 runs, so it goes during my filter cycles too. It also eats my FC. I’ve considered just disabling it but I’ll probably just let it go and then not replace it when once it kicks the bucket.

Thanks for the help!

 

[phonedave]

Thanks! It’s from the dealer. The top is like a sunbrella type fabric. The underside which is bleaching a little looks like vinyl.

That is what mine is. I took a closer look at it over the weekend and it appears to have bleached. It used to be a light grey, but where it is above the water it is much whiter and a little rougher.

 

[elbow]

That is what mine is. I took a closer look at it over the weekend and it appears to have bleached. It used to be a light grey, but where it is above the water it is much whiter and a little rougher.

Thanks! How old is your cover?

 

[phonedave]

Thanks! How old is your cover?

18 months give or take.

 

[elbow]

18 months give or take.

Thanks! Last question. Do you ever treat the top with anything? I’m thinking of giving this a try in the spring:

 

[phonedave]

Thanks! Last question. Do you ever treat the top with anything? I’m thinking of giving this a try in the spring:

View attachment 552264

I have not treated the cover, but I hear good things about 303

I think I will use it this spring. I am going to find a mild detergent and a soft brush and clean the cover and then treat it. It took a beating this winter. For some reason, birds seem to like to sit on it and do what bird tend to do.

 

[Mdragger88]

303 is good stuff
I use the vinyl 303 for the top of my vinyl cover a couple times a year & it looks like new after 5 years. I also use it on my vehicles.
I previously used the 3m stuff for outdoor cushions & such but have finally run out so I plan to get the fabric 303 stuff for their treatment this spring.

 

[Cousinvinny]

If it's the Sunbrella like fabric, this is what I was told to use. I believe that's what came on my Bullfrog tub.

Robot or human?

 

[elbow]

If it's the Sunbrella like fabric, this is what I was told to use. I believe that's what came on my Bullfrog tub.

Robot or human?

This looks like it's primarily for vinyl, leather and plastics though. The 303 I posted is made specifically for fabric.