Rain

[riley00dog]

We are currently receiving significant amounts of rain and it’s set to continue for at least the next week. It’s the first real rain we have had since the pool was built. Is there anything I need to do chemistry wise out of the ordinary? The cover is on and much of the rain seems to flowing from the cover straight into the skimmer box and out of the overflow drain. Overflow is currently coping nicely. Ph has pushed up a little so I’ve knocked it back down. Just wondering should I raise the FC level? Drop the ph? Last time we had rain I had a pool full of worms. Have sent the robot on a cycle under the cover but he may not complete his cycle as he doesn’t like running with the cover on.

 

[needsajet]

Good to hear the overflow is doing it's job Mine gets blocked by leaves occasionally, so I watch for that.

Nothing special chemistry wise, just slightly more FC consumption due to anything getting washed in (or wriggling in! lol). Sounds like you have it well under control.

If the fresh water mostly sits on top and flows out, the chemistry impact is almost unnoticeable. If water is mixing, your CYA, salt and CH will drop by way of dilution (some leaving via the overflow), but it will probably be a very slow reduction. I'd like my calcium to go down a bit before summer, so I drain down and then let the rain fill up the pool, or at least run the pump now and then so water with calcium is draining off.

 

[Costas > DownUnder]

If the fresh water mostly sits on top and flows out, the chemistry impact is almost unnoticeable. If water is mixing, your CYA, salt and CH will drop by way of dilution (some leaving via the overflow), but it will probably be a very slow reduction.

Needsajet is on the money...

This is what I noticed over winter where I had to perform a couple of back washes due to rain filling up my pool.

Dilution of some of the chems was the only thing I really noticed and that was fairly slow anyway.

 

[duraleigh]

If you use your pool pump to lower the water level, it is probably a little better idea to use the "vacuum to waste" setting (of course assuming you have a multiport) rather than backwash. Some of that depends how MUCH you need to lower the water.

Maybe do both......do a normal backwash and then go to "waste" for the remainder of your draining.

The filter manufacturers seem to think backward flow through the laterals for a really extended period of time is not a great idea. I can't remember their reasoning but I did see it as a suggestion.

 

[riley00dog]

Good to hear the overflow is doing it's job Mine gets blocked by leaves occasionally, so I watch for that.

Nothing special chemistry wise, just slightly more FC consumption due to anything getting washed in (or wriggling in! lol). Sounds like you have it well under control.

If the fresh water mostly sits on top and flows out, the chemistry impact is almost unnoticeable. If water is mixing, your CYA, salt and CH will drop by way of dilution (some leaving via the overflow), but it will probably be a very slow reduction. I'd like my calcium to go down a bit before summer, so I drain down and then let the rain fill up the pool, or at least run the pump now and then so water with calcium is draining off.

Thanks [emoji4] I did bump up my SWCG a little just before as I thought it can’t hurt and I will have extra organics to deal with. Hoping it drops my ch a little too. Will keep an eye on levels but good to know it shouldn’t be a sudden change. I just bumped my cya to 80 2 weeks ago.

The overflow was well worth the $460 I paid to have the plumber come and fix hubby’s dodgy job. It works like a dream. Will watch for leaves blocking it though. The whole outdoor area is so much drier now the pool and surrounding drains are in. It was hard to know how well the drainage we put in would work, but it seems to all be managing well. Will see how it all holds up over the next week.

It’s so cold here. I think top of 17* today. The more I anticipate swimming the colder it seems to get [emoji849]

 

[riley00dog]

Needsajet is on the money...

This is what I noticed over winter where I had to perform a couple of back washes due to rain filling up my pool.

Dilution of some of the chems was the only thing I really noticed and that was fairly slow anyway.

Great! Thanks Costas. It’s been so dry here that I hadn’t given much thought to torrential rain and the impact it might have on the chemistry.

 

[riley00dog]

If you use your pool pump to lower the water level, it is probably a little better idea to use the "vacuum to waste" setting (of course assuming you have a multiport) rather than backwash. Some of that depends how MUCH you need to lower the water.

Maybe do both......do a normal backwash and then go to "waste" for the remainder of your draining.

The filter manufacturers seem to think backward flow through the laterals for a really extended period of time is not a great idea. I can't remember their reasoning but I did see it as a suggestion.

Thanks, great advice. It does make sense that extended backwashing might not be good for the filter. At the moment the overflow is managing well, with capacity to handle more. It’s good to know what I need to do though if it can’t keep up.

 

[Costas > DownUnder]

Thanks, great advice. It does make sense that extended backwashing might not be good for the filter. At the moment the overflow is managing well, with capacity to handle more. It’s good to know what I need to do though if it can’t keep up.

If you can time it right ie. if filter is dirty etc you can use the added rain as an excuse to perform a normal back wash of the filter.

BTW - My daughter and I jumped in today.... water was around 25C, so still a bit cold for 'dad' but daughter loved it...

28C and Sunny tomorrow so the solar will be working overtime...!

 

[riley00dog]

If you can time it right ie. if filter is dirty etc you can use the added rain as an excuse to perform a normal back wash of the filter.

BTW - My daughter and I jumped in today.... water was around 25C, so still a bit cold for 'dad' but daughter loved it...

28C and Sunny tomorrow so the solar will be working overtime...!

Will do!

That’s so good to hear that your daughter got to swim today! I hope she has great time tomorrow too. For once I’m jealous of your weather [emoji6]

 

[Dirk]

Leaves clogging overflow? Could that benefit from building my invention? Somebody's got to, and it ain't gunna be me!! (I don't have the kind of overflow that gets clogged, or I would.) This guy said he was going to, but I never heard back if he did or if it worked...

OK, apparently this concept was invented before I thought of it, but I'll still take the credit and the $119.99!

How do I keep leaves from blocking my overflow drain...

 

[DuaeGuttae]

You mention “significant amounts” of rain continuing for a week, so I thought I’d share what has happened to my pool with some remarkable rainfall in the past six weeks.

We’ve only owned the house with the pool for about a year. I’m not sure how the previous owners handled things, but the chemistry and equipment both needed work when we got them. We had some pretty significant stained calcium scale on the pool surfaces, which is gone now. I’ve found TFP to be a very valuable resource in managing my pool water, and the Pool Math calculator has been great for helping me know how to keep things balanced. We have naturally high calcium (250) and high alkalinity fill water. The previous owners also left an empty bucket of Cal-Hypo behind, so it was probably good that my levels were only perhaps 575 at the start of the season. (I have a hard time figuring out when the color stops changing even using the fading endpoint protocol.) I had to knock my pH down with muriatic acid on a regular basis once pH got to 7.7 or I’d see calcium form on the SWCG plates. Before I was closely watching CSI, I actually saw flakes coming out of the spa returns.

Anyway, that’s the background. At the beginning of September we started getting lots of rain, inches at a time for days. Usually our overflow keeps up, but there have been three occasions that torrential downpours raised the pool high enough that I drained (one of those let me do a free backwash that someone mentioned). We also lost power several times at the beginning of all this, so I put some trichlor tabs in a floater to help maintain things since the SWCG would be off for hours. (My CYA was already a bit low before the rain, and it was good for me to practice with tabs and see how they dissolve since I had had no experience with them.)

After 22 inches of rain (about 2/3 of the average annual rainfall), my calcium level has dropped to 375. My salt went from 3200 to 1800. My alkalinity hit 50. I started having to let the pH stay in the upper 7’s instead of driving it back down. As the temperature has dropped, I’m really needing to watch CSI. I actually boosted the TA a bit before bringing the salt level back up to keep the CSI from going too low. I used to dread seeing 7.7 on my pH because I didn’t want to do that acid thing again. Now it’s just fine.

All of that is to say, you’re getting good advice about checking chemicals and watching for dilution, but if the rain is really, really significant, it certainly can have a really, really significant effect on pool chemistry. In my case it has been good because of calcium and alkalinity, but if you’re more properly balanced, it might not be so good. I think the prevailing wisdom that the pool doesn’t care if it rains is pretty good, but keep in mind how significant your rain totals are. I for one am glad to have a way to measure rainfall so that I have a little confirmation that I’m really seeing those changes when I run my tests.

I should perhaps add that my water has not gone green or cloudy at all in response to these weeks of rain. Three cheers for chlorine! Yes, there have been more leaves and dirt (and it’s annoying that the rain has made it hard to find a time to put my new robot in the pool). We have been using our leaf net, though, and that helps.

It’s the end of our summer here, and the one negative was that the rain cut short our swim season. The land really needed it, though, and I enjoyed the cooler temperatures. We’re due for more storms tomorrow and then colder weather, so we really are probably done swimming. Have fun as you get started with your season!

 

[riley00dog]

You mention “significant amounts” of rain continuing for a week, so I thought I’d share what has happened to my pool with some remarkable rainfall in the past six weeks.

Thanks for sharing your experience. It is interesting to hear what all that rain did specifically to your levels. I think I will definitely need to add salt as I was getting close to needing some at last test. CH I’m happy if it comes down a bit but not too much, so we will see there. TA has room to move down a little. I think I’m currently at 70. We’re on about day 4 of rain. We had a couple of huge storms earlier in the week but now just consistent rain. No power black outs yet and it is very rare for us to have them as we have underground power, although it has happened when a substation has been hit. I think we got about 50mm (2 inches) yesterday and expecting about the same today. Not sure what amounts we will be receiving after today but it looks like we’re in a pretty set holding pattern for at least the next week. I will test the water when/if there’s a break. The most promising thing you mentioned is that your water didn’t go green. I have my fingers crossed for the same outcome. We leaves in the pool at the moment as it’s quite still. We only see them when it’s blowing a gale. So sad that you are at the end of your swimming season [emoji22]

 

[riley00dog]

Leaves clogging overflow? Could that benefit from building my invention? Somebody's got to, and it ain't gunna be me!! (I don't have the kind of overflow that gets clogged, or I would.) This guy said he was going to, but I never heard back if he did or if it worked...

OK, apparently this concept was invented before I thought of it, but I'll still take the credit and the $119.99!

How do I keep leaves from blocking my overflow drain...

Thanks Dirk! One day you will make a fortune with your inventions. Your acid dosing contraption certainly had a lot of R & D behind it. Right now not a single leaf in the pool but I will keep it mind.

 

[spoonman]

If you use your pool pump to lower the water level, it is probably a little better idea to use the "vacuum to waste" setting (of course assuming you have a multiport) rather than backwash. Some of that depends how MUCH you need to lower the water.

Maybe do both......do a normal backwash and then go to "waste" for the remainder of your draining.

The filter manufacturers seem to think backward flow through the laterals for a really extended period of time is not a great idea. I can't remember their reasoning but I did see it as a suggestion.

Good to know. I understand that laterals are somewhat delicate although I’ve never worked on them. I have heard that prolonged reverse flow can cause “channeling” in the sand, which could hurt filtering capabilities. This may or may not be part of the manufacturers concern. Don’t know.

My sand filter has a slide valve (push/pull). Here in Phoenix we recently had 3” of rain. As a result I had to backwash for about 4 minutes to reduce the water level a few inches. Don’t think this did any damage (would I even know?) but I will be more mindful of the laterals going forward.