EEEK! The Monster Behind Our Pool Light

[Caracat]

It is SLAM day 7 for us. Still losing vast quantities of chlorine, though the pool looks gorgeous.
Everything has been well-scrubbed except behind the pool light, which I could not remove. My husband finally got it free today. And we found this. It is super lumpy, bumpy, black, green, gray up in there. I haven't gotten in the water yet to see how far back it goes and how bad it really is. My hairdresser had a fit after she saw the state of my hair after jumping in this hyper chlorinated water to scrub algae all week. She made me promise not to do it again. How in the world do I go about cleaning out this nightmare mess? Help!

 

[YippeeSkippy]

how about a long pole with a brush on it? Either standing on the edge of the pool or in as deep as you can go (save the 'do!). Or rent a kid to do it with goggles, good brush and chlorine.

I wonder if you can hook up a manual pool vac to help remove the schmutz as you scrub, so you aren't adding all of that to the general water in the pool? Just a thought....
Maddie

 

[CarolineM]

Bathing cap will protect your hair.

 

[Divin Dave]

Oh yeah,
Ive seen ugliness like that before. Lots of other TFPers have too.
a good brush will do the trick and like Maddie, said, hook a small brush to something long and skinny and work it up onto the conduit as much as you can.

Then keep on slamming.

 

[Caracat]

My biggest concern is how bumpy it is. The variance between, “mountains and valleys” is over an inch, and there are many sharp edges and porous, rough spots. Even if we get all the funk out how in the world will we keep it from growing back in that environment? We have a lot of little pits & bumps all over the whole pool. I’m starting to think we will have to drain and replaster the whole dang thing. How does one determine when that is necessary?

 

[chiefwej]

Maintaining proper water chemistry keeps it from growing back. In the 13 years I’ve had my pool, I have removed the light twice to replace the bulb. Both times, I found nothing behind the light fixture other than a bit of dirt and grit. But then I have never had any algae anywhere in the pool.

 

[Divin Dave]

If I were you I would leave the light loose and floating until you are algae free.
Part of slamming is to brush the whole pool. A lot of people skimp on that part and have a hard time completing the slam.

When algae attaches itself to stuff, it then grows a biofilm over itself which helps protect it. Brushing breaks that protective bio film and allows the chlorine to work to kill the algae quicker.

To get rid of algae takes patience and commitment to following the slam instructions precisely. Unfortunately its doesnt happen as quickly as we would all like it to.


Once you rid the pool of algae, its imperative to maintain the FC/CYA levels. If you do that, you wont get any more algae again. Since we now know what is behind your light, I would make that a yearly maintenance task to open that up and clean also.

 

[Caracat]

SLAM day 10. Here are my FC losses by day.
1) daytime: 39.5 overnight: 8
2) day: 31, night: 4.5
3) day: 30.5, night: 5
4) day: 24, night: 5
5) day: 16.5, night: 4
6) unknown, ran out of R-0871 (dozens of army worms falling in the pool, are they attracted to chlorine!??)
7) day: 16.5, night: 6 (day we found the mess behind the light, army worms keep coming)
8) day: 18.5, night 5.5 (no more army worms, that was weird!)
9) day: 20.5, night 5.0 (temps dropped from high 80s to 60s degrees, LOTS of rain)
10) Today. Off to buy chlorine again.
Y'all, I really need to leave the house and do so many other things! Tell me this is ever going to end.
Also, can I turn off my poor pump for a while? I think it needs a break.
Thanks! Cara

 

[pookiesunshine]

The gunk behind my light looked similar but was soft, easily vacuumed. i hooked up an old manual vacuum hose to my skimmer, put filter valve on waste, sat on a paddle float in the pool, and manually vacuumed as much of the gunk out as i could. I see you have a de filter and likely dont have the ability to vacuum to waste right now, but you probably have enough pipe run available to install a three-way valve between the pump outlet and filter inlet. that would give you the ability to vacuum to waste. just a thought. of course you could vacuum to the filter but ugh.

 

[borjis]

SLAM day 10. Here are my FC losses by day.
1) daytime: 39.5 overnight: 8
2) day: 31, night: 4.5
3) day: 30.5, night: 5
4) day: 24, night: 5
5) day: 16.5, night: 4
6) unknown, ran out of R-0871 (dozens of army worms falling in the pool, are they attracted to chlorine!??)
7) day: 16.5, night: 6 (day we found the mess behind the light, army worms keep coming)
8) day: 18.5, night 5.5 (no more army worms, that was weird!)
9) day: 20.5, night 5.0 (temps dropped from high 80s to 60s degrees, LOTS of rain)
10) Today. Off to buy chlorine again.
Y'all, I really need to leave the house and do so many other things! Tell me this is ever going to end.
Also, can I turn off my poor pump for a while? I think it needs a break.
Thanks! Cara

The pump has to run at all times til the slam is done, otherwise it will lengthen the process.

what is your cya level currently?

I ask because it looks like you started the slam at a FC of 39.5 and it's dwindled down to less
than half. You have to keep and maintain the high level of your FC to CYA ratio otherwise
the algae cannot be eradicated and thus your slam goes on and on.

 

[Dirk]

Please be careful about poking around in your light niche. There is another thread going here about a guy whose ground lug broke off, due no doubt to some amount of force applied to it and its age. It was probably corroded and when one of his pool workers did something to it, it snapped off. So now he's had a heck of a time repairing that. If all the wires that come out of the niche's conduit run into the light housing, you're probably OK. But if you see any wires coming out of the conduit and connecting to the niche, maybe under a big glob of sealant, that's what you have to guard. That sealant is protecting the underlying connection from water and corrosion, and at the same time protecting your pool surface from staining from the result of that connection corroding. If you compromise the sealant, or manage to break the whole thing off, you're going to have the same problems the other guy does making that right.

It was mentioned to try and vacuum while cleaning out the niche. Personally, I would not go poking around in the niche with anything without completely shutting down the power to the pool. Everything, not just the light. Like the entire sub panel to the equipment pad, back at the main breaker box. This is likely overkill, but that other thread links to a story about a guy who died messing around with his underwater light while in the water. Farfetched in your case? Maybe? But it's something electrical. And it's water. And you're touching both. Pretty simple math...

 

[JohnT]

My biggest concern is how bumpy it is. The variance between, “mountains and valleys” is over an inch, and there are many sharp edges and porous, rough spots. Even if we get all the funk out how in the world will we keep it from growing back in that environment? We have a lot of little pits & bumps all over the whole pool. I’m starting to think we will have to drain and replaster the whole dang thing. How does one determine when that is necessary?

Chlorine and lack of light will keep it from growing back. Algae requires sunlight to grow. Some kind of crud may be growing behind your light, but normal pool chlorine levels will take care of anything that might enter the pool.

 

[Caracat]

The pump has to run at all times til the slam is done, otherwise it will lengthen the process.

what is your cya level currently?

I ask because it looks like you started the slam at a FC of 39.5 and it's dwindled down to less
than half. You have to keep and maintain the high level of your FC to CYA ratio otherwise
the algae cannot be eradicated and thus your slam goes on and on.

My CYA level is 55. I have been keeping the FC at 24, adding bleach about every 3 hours. The numbers above are the total amounts of FC lost each day since I began. (I record my tests every 3 hours, then add up all the losses at the end of the day over a 12 hour period.)

 

[Caracat]

Please be careful about poking around in your light niche. There is another thread going here about a guy whose ground lug broke off, due no doubt to some amount of force applied to it and its age. It was probably corroded and when one of his pool workers did something to it, it snapped off. So now he's had a heck of a time repairing that. If all the wires that come out of the niche's conduit run into the light housing, you're probably OK. But if you see any wires coming out of the conduit and connecting to the niche, maybe under a big glob of sealant, that's what you have to guard. That sealant is protecting the underlying connection from water and corrosion, and at the same time protecting your pool surface from staining from the result of that connection corroding. If you compromise the sealant, or manage to break the whole thing off, you're going to have the same problems the other guy does making that right.

It was mentioned to try and vacuum while cleaning out the niche. Personally, I would not go poking around in the niche with anything without completely shutting down the power to the pool. Everything, not just the light. Like the entire sub panel to the equipment pad, back at the main breaker box. This is likely overkill, but that other thread links to a story about a guy who died messing around with his underwater light while in the water. Farfetched in your case? Maybe? But it's something electrical. And it's water. And you're touching both. Pretty simple math...

Thanks! There is no power to the light. When my husband finally got the screw out of the rim the fixture floated across the pool, the unstripped/cut cord still attached. The fixture looks brand new, and I think the previous owners put it there just to fill the hole with something. I would prefer some sort of alternative cover to a useless light, but I haven't been able to locate anything like that.

 

[Caracat]

The gunk behind my light looked similar but was soft, easily vacuumed. i hooked up an old manual vacuum hose to my skimmer, put filter valve on waste, sat on a paddle float in the pool, and manually vacuumed as much of the gunk out as i could. I see you have a de filter and likely dont have the ability to vacuum to waste right now, but you probably have enough pipe run available to install a three-way valve between the pump outlet and filter inlet. that would give you the ability to vacuum to waste. just a thought. of course you could vacuum to the filter but ugh.

Thanks! I held the vacuum hose and sucked the muck to waste while my husband scrubbed out the hole with a variety of brushes. It's still nowhere near clean looking, but it has been thoroughly scrubbed. The darkness that remains isn't budging, so I think it's just a big ugly stain now as opposed to algae or other contaminants.

 

[YippeeSkippy]

Thanks! There is no power to the light. When my husband finally got the screw out of the rim the fixture floated across the pool, the unstripped/cut cord still attached. The fixture looks brand new, and I think the previous owners put it there just to fill the hole with something. I would prefer some sort of alternative cover to a useless light, but I haven't been able to locate anything like that.

One option- Light Doctor Disc-Frank Wall Enterprises

Ridiculously overpriced, IMO, but perhaps seeing this you can find a cheaper version?

Maddie