Algae on solar cover from rain water

AndyTN

Bronze Supporter
Mar 27, 2019
463
Memphis
Pool Size
26000
Surface
Vinyl
The only time I have ever had algae in my pool has been while I was on vacation with the with my solar cover on the pool. It rained an inch and after the rain water sat on top of the cover for a week, green algae started to form. With a decent amount of water on top of the cover, there's no way to prevent water from spilling into the pool when pulling it off. My pool immediately turned a cloudy green color and it was pretty easy to clear up in 2 days with SLAM but just a big inconvenience right when returning from vacation.

Does anyone have any methods for preventing this while on vacation? When I am at home and using the solar cover in Spring and Fall, I will brush the water off after rain but this is not possible while on vacation. I have tried using a pump sprayer to spray SLAM-level water proactively on top of the cover but this doesn't seem practical for more than a few days or if we get a heavy rain.
 
When I replaced my solar cover 2 years ago, I also installed solar cover grommets. This seems to help keep some of the water off the solar cover and when I roll it up, any water retained will drain. This may help you too. Example: Quick Drain Grommet System - Set of 6 - PoolSupplies.com (This isn't what I purchased, but the result of quick search.)
 
Some good comments already.

Your proactive slam spray sounds like a good idea prior to leaving. I assume you start with pool water to pick up the cya then add chlorine.

I'd repeat the pump spray upon returning but this time use 10x slam level. I do that randomly through the year when my cover gets grimy. Maybe also bump the pool fc level upon returning to finish off anything coming from the cover.

For a crazy idea what about just removing the cover prior to vacation?
 
When I replaced my solar cover 2 years ago, I also installed solar cover grommets.
This is exactly what I need and installing about 10 of these should prevent large puddles from forming. I will get some of those now before I forget come September when I put the cover back on. This should also prevent me from having to brush off the water on top when I am at home. Thanks for the tip.

Is you blanket to big and folded up against the sides ?
I smooth it out as much as possible but there are always some minor air bubbles and wrinkles. The rain finds itself in between the slightly higher spots and then starts to accumulate into puddles up to an inch or so deep. When I'm home, it is easy to brush them off.

I'd repeat the pump spray upon returning but this time use 10x slam level.
For a crazy idea what about just removing the cover prior to vacation?
Good call on the super-chlorination when there is some visible grime/algae on the cover which should kill a lot of it sitting for a few hours.

Come about end of March beginning of April down south, we get warm spells where it feels amazing in the upper 70's and you desperately want to jump in even if it is very cold. I'm just worried taking off the cover for 6-8 days will cause me to lose 5-10 degrees and will be make or break for those early Spring cannonballs with the kids. I also have a bunch of oak trees all around my pool and the cover helps keep out most of the Crud falling out of the trees during bloom.

Everyone who replied to my post is from up north and I assume you all use your solar covers for most of the year having a lot more experience than me. I'm not going to bother investing in a heater, whether solar or gas, when I put my solar cover away in late April and have warm water until October. I'm at the point right now that my pool temp is in the high 80's and I'm going to hook up my home made fountain to start cooling off the water.
 
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Here is my thought on the solar cover! Last year, I used my cover (maybe 2nd season) in where it was left on the pool for days upon days. After a few days, I would see algae forming in spots (some members disagree, but I can tell you that the cover was causing the algae). Cover on, algae showed up, cover off, no algae. Levels were the same, nothing different.

Now, skip ahead towards the end of last year. I cut 1' all the way around (where there is a gap of 2') in the middle of the pool and 1' around the outside (cover cut in half). Well guess what? No algae whatsoever this year.

The only disadvantage is that there is heat loss on the outside with a smaller cover (covers 80% of the pool), but no algae. What I would recommend is to peel the cover back (at least 1/2 of it for a few hours during the day), and keep your levels at 10% of your CYA as this should help. Algae on top of the cover should not happen as evaporation through wind and heat should remove most of the water. If you do not have a main drain, this also could restrict water flow. There are a lot of members who have reported success for weeks out with a solar cover in the mid 80's and no problems. Some members put covers on and a few days later, algae shows up.

For me, at least I have no algae, but losing heat. One other option is to keep normal levels and dose the pool with Poly 60 (which we usually do not recommend), but in this case may work. Chlorine, and only chlorine 99% of the time is fool proof.
 
Princess Auto "Power Fist" brand Tarp Eyelets which essentially will do the same job as the solar cover grommets. These will install the same way. I would put them on the seams. They have a 1/2 inch hole. I use them to install a pull rope as well. FWIW the Eyelets are solar cover colour blue made of polypropylene.
 
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Princess Auto "Power Fist" brand Tarp Eyelets which essentially will do the same job as the solar cover grommets. These will install the same way. I would put them on the seams. They have a 1/2 inch hole. I use them to install a pull rope as well. FWIW the Eyelets are solar cover colour blue made of polypropylene.

I understand that you used the eyelets, but what exactly are you doing? Do you have rope to pull out of the pool, etc? The easiest way I found is to roll up with the PVC. Next go around, I will cut the cover into 3 pieces. They will be 1/3rd of the pool with 1' overlapping, maybe 6". This way, the 10' PVC will work and rolling up will be faster so there are no creases. If you have a picture, please upload it. Thank you.
 
So far I have only started installing eyelets. I only use the rope to pull the cover onto the pool. It does not aid in removing the cover. The reel is fine for that. Once I remove the white protective sheet from the rolled up cover I simply grasp the rope and walk the cover down the length of the pool. Easy. I prefer to keep the cover in a single piece. We get wind storms that could get under smaller pieces. The take up reel does a good quick job of removing the cover.
One shot shows how the rope is attached. The double eyelets reduce stress on the cover. I tie the rope in a knot [not seen] and the rope coming up from under helps to lift the leading edge of the cover while you position it.
I want to use eyelets positioned along any areas that puddle with rain. I have not done this yet.
 

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Excellent idea. One has to find what works best for them. The cover is a real PIA to take off (no matter how you look at it), but the way I look at it is that 3 hours less on the heater daily, saves $3 per day, and possibly less pump run time. I like your reel and idea. Thank you.
 

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You are very welcome Catanzaro.
Please realize that this is a 40 foot long x 17 foot wide pool with a 19 foot round end. I purchased an 18x40 foot solar blanket so that the round section could be included as a single piece. The stairs are covered from the cut off.
I never found it hard to use the take up reel to remove the cover. My last pool also had one. I assumed everybody used them.
Covering the pool was another issue. Yes a PITA, without the rope. Now I can do it myself.
BTW, the weight of the cover on the reel keeps the base in place. I don't even have to lock the wheels.
 
Okay then I just went for my first dip of the season. It is Canada Day so it is my duty I think.
I opened the pool and dumped todays 1/2 inch of rain water. After a few laps I could see my hard gained heat going up in steam.

The one hole in the bubbles actually fills up with water.

This cover is going to be replaced on warranty so I will experiment with the eyelets to see if they actually work.

Back to you in a few.
 
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