Do I need to acid wash? Edit: Now clean, with pics!

KenV

0
Jul 2, 2010
30
Quick description of my situation: We bought the house in 2008 and were told it had a two-year-old plaster refinish on its surface. We didn't plan to use the pool for at least a year (repo house = tons of work with little free time) so we simply added trichlor when the water went cloudy. When I was unable to care for the pool due to illness in mid-2009 it greened, then blackened. We kept most of the monsters at bay with trichlor powder (not enough I guess) and monitored the filter/pump strainer, cleaning as needed.

FF to now: Not thinking about the heat coming, I pumped the pool out last week, down to the last 1.5' of the deep end. Our initial plan was to drain/scrub/muck/acid wash/refill it, but after asking around I'm not sure that I need to (or even should) acid wash it at all. (I tried a couple of test areas, finding success, then rinsed heavily within 15 seconds. Hopefully I didn't damage the plaster too much.) The heat is going to reach 100 this week, so now I'm thinking we should just muck it out and treat the plaster differently after refilling it...we could probably have it at least mucked/scrubbed and refilling by Wednesday. Let me know if pics will help with the diagnosis/treatment here and I'll take/post them this afternoon.

As of Saturday I have the 100XL test kit on hand for the post-refill testing (holy cow, that's a comprehensive kit!), so all I need is some direction. I don't want to kill the plaster with acid, but I'd like to get it as clean as possible before refilling, unless that's not as necessary due to what is possible with proper chemical balance and future maintenance of the entire pool and its equipment.

Sorry for the spew/redundancies here. I'm on a break between service calls and would like to get the knowledge ball rolling with TFP. It's 1315 here in California and I'll be home by 1430. Any questions/data/jeering/photo requests would be much appreciated. Apologies if I missed any FAQ. I'm here whenever I have the time but that has been hard to come by lately.

Thanks for anything you folks can tell me!

K

PS I have a good pressure washer on hand if that helps with determining how I should handle the issue, pre-refill, with time scarcity and the hot weather being my concern.
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

Consider a photo request officially filed! Of the plaster pre- and post-test acid wash, if possible. If you don't have lots of calcium scaling or horrible copper stains, you won't need an acid wash. After you refill and clear the algae, ascorbic acid can take care of iron, and chlorine will remove organic stains.
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

MITS:

Thanks for the fast response and tech. I just pulled in the drive and moved the pump into the deep end near the muck, which is more shallow than expected. More clear water than anything else. Also, much of the buildup on the walls became algae jerky and fell off, leaving some brown algae residue. I'll get pics in a sec here.

BTW no cracks yet, so I called my better half to tell her we have a busy 48 hours ahead of us. Well, work aside. Back in a bit.

Edit: Just snapped a few. I think I'll dub this project "The Dead Pool":

Pool shot:
IMG_3615.jpg

The sump, I mean deep end:
IMG_3618.jpg

Acid drip by seat in deep end. 5sec of acid drip, immediate irrigation with soaked wet brush. Done while pool was more full:
IMG_3619.jpg

Another test drip, over near the diving board:
IMG_3617.jpg

Shallow end, just using the brush:
IMG_3630.jpg

More shallow end, more brush-only:
IMG_3629.jpg

Weird stain #1:
IMG_3628.jpg

Weird stain #2:
IMG_3627.jpg

Weird stain #3. I recall a tablet, or chunks thereof, ending up there:
IMG_3626.jpg

Tub, in much better shape:
IMG_3621.jpg

This small step received acid for about ten seconds, then irrigation. The pic doesn't show how clean it really is:
IMG_3620.jpg

Equipment room shot. Fear me and my dust bowl. I sweep it up, more blows in. So it is near farmer's fields I guess :
IMG_3622.jpg

Furnace:
IMG_3623.jpg

Chems. Not all of them, and not the most important part, the test kit. That's next to the laptop....man, I really need to clean that room:
IMG_3624.jpg


That's what I have so far. If I should just muck the deep end, power wash the whole thing and refill asap, I'm cool with that. I just don't want cracking or plaster caving in Indiana Jones-style. Again, much thanks for any assistance.
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

Nice pictures! You can handle this.

It looks like mostly organic staining to me. Does the plaster feel very rough? It's hard to tell how good/bad shape it's in since it's so dirty in most places. Where you pressure washed the floor it doesn't look too bad to me. Weird stains #s 1 and 2 look like they could be copper; #3 maybe iron? Most of it is definitely brown organic gunk. How's the integrity of the plaster? Any bubbles/delamination/loose spots?

I would try and get water back in that thing as soon as possible, since it's so hot. You could try spot treating those weird stains while you have the water level down, but there are likely others that are similar but still buried in sludge. Hopefully some other folks will chime in soon!
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

Thanks for the confidence Melt. It looks better after drying out a bit.

Details: The plaster isn't sandpaper-rough, actually quite smooth on the floor. That floor was brush-only btw. I only used the pressure for a bit below the tiles. The sides feel rougher than the bottom, but nothing uncomfortable, if that makes any sense. I can't find anything 'soft' or coming apart. No chips, no cracks, no crumbling. The deep end is the only place left to check.

We tried copper a while ago, before I knew it wasn't a good idea. Maybe that stained it, but I mixed the copper with water in a bucket before walking it around. I was thinking that the black stains are old algae and will try the puck/vitamin C tricks once there's water in there.

I'll probably be able to take more pics after we muck it tonight. I think we can knock out the power wash/mucking tonight and start the refill. +1 on anyone else chiming in. Well, if I stare at it the thing gets worse so I'm going to run a couple of miles while it pumps down and the sun drops a bit. Clear the head, you know. Thanks Melt.

K
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

A good power washing is just the thing. You won't be able to be sure what else is required until after that. I suspect that power washing will clean up nearly everything.
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

I hate to be the one to tell you, but that is very old plaster :cry: Whoever told you that it was 2 years old lied :evil:

Do the best you can to clean it up (maybe use some TSP) and DO NOT ACID WASH it! You will absolutely destroy what remaining life you have in the plaster with an acid wash.

Get it clean and get water in as soon as you can, especially if the heat is coming your way. That will not do you any favors either.

Welcome to the 'page!
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

Power washing it is. Glad I bought the Karcher a little while back. Thanks Jason.

Darn appraiser. lol, no use crying over spilled Morgan I figure. The bottom does look old, as it's remarkably smooth. I guess it was maintained to some extent before the foreclosure, as I didn't find any structural blems (yet). It looks a bit thin on the bottom, but we plan to make the best of it and resurface after paying off the cars. No way am i getting into $5K or more of expense this year if it isn't paying something off. In any case, thanks for the tech Bruce.

From here it's a power wash and refill, followed by initial chemical testing and a full cleanup of the pump and filter. At least all that works. We won't complain, as we bought the house at %50 off. A challenge to go with the blessings, I figure.

I'll update or post a new thread linking this one after the cleanup is done. Should be a hoot!
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

Be careful how close you get with the power washer (the spa looks like you already have some delamination starting). You can remove the plaster if it is high enough psi and you hit soft spots.
 

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Re: Do I need to acid wash? Plaster pool w/interesting stains

Can you tell me where you think it's delaminating? I'd like to think we can get whatever the power washer doesn't remove with shock and brushing later. I know the pool won't look brand new when the refill is complete but want to remove as much as I can with the thing. I was 1/2" away when I shot the upper edge of the pool and didn't see anything getting loose aside from gunk. The Karcher is an 1800psi unit, not the big one. Thanks for whatever you can tell me Bruce.

PS I wonder how old the plaster actually is. It was appraised in the fall of 2008, so now it's about 4yo by his estimate. If these things last only 7 or so years we'll set aside some cash starting now. heh
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

Both sides of the spa step appear to be letting loose from the pics. It may be algae (or my old eyes :shock: ) though.

From the looks of the tile and the drain covers, I would say that pool is at least 15 years old, and the plaster is too! The filter looks like it might be an old Anthony filter (can't really tell from the photo, but the color is close!), and it looks original also. The pump and heater have obviously been replaced some time ago, as they are not the originals.

Plaster should last you 10 years currently; more if you take really good care of it. That just looks like 15-20 year old plaster to me.
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

Thanks for your candor Bruce. I've cleaned it up and still don't see any cracks, so at least it won't fall in this year :D

There are several lines in that spa, and all are algae lines. I test-ran the pump in there, then switched to the pool, then back to the spa. That made for some strata in the algae. I don't find anything when I run my hand over it, at least not pre-pressure wash. This will probably be the only pressure wash it gets before getting resurfaced. We'll research our options then.

Baby's asleep, gotta get back out there!

Edit: You're correct on the filter. It's an Anthony Apollo. I already have the glue gun loaded for when we yank that apart :party:
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

Hey folks.

I'll be home in a few hours and will finish the pressure wash to allow for the refill. Is there anything I need to do to the system before starting the refill? I plan to clean the pump strainer and the DE filter, but wanted to know if there is anything to gain from flushing anything else.

I'll shop-vac the last bits of goo from every fitting, clean the eyeballs, etc., before refilling. Any info appreciated. Also, if there's a bare minimum of chlorine to add before I start baseline testing please advise. Gotta run but will check this when I get home. I'm pumped, pun intended :D
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

Just spent 45 minutes with the blaster. Good news, bad news, other news:

Good news: Almost everything comes off! I'm at the top of the deep end at less than an hour invested. Also, very little plaster damage. Lastly, some VERY dark purple areas that had dead black/purple algae sitting on them are lightening every minute. From 20' away the pool looks quite nice, really.

Bad news: A little plaster is coming off here and there, so I have backed off on distance with the nozzle. I have a bunch of flecks of plaster on my arms, but that's after almost 1/2 of the pool. Also, it appears that I can almost see through the pool bottom, so even though there are no cracks or large chips so far, we'll probably replaster at the next refill in a couple of years. (Edit: On closer inspection after the pressure wash, it appears the plaster isn't that thin. It's just stained all to heck.)

Other news: The areas I tested with acid look incredible, as in bright white. No plaster residue below the areas, so maybe the etch I tried was fast enough.

I don't know if more pics matter now, so I'm going to weigh the merits of a very light acid wash (10:1 instead of straight up) and forge ahead after dinner. Any criticism/suggestions still happily taken. Thanks.
 
Re: Do I need to acid wash? Plaster pool w/interesting stains

Update time, since it's been filling for a few hours and I'm a bit beat:

I felt an 8' x 10' area of the pool surface actually pushing up from the concrete when I went in this morning. I jumped back and found no damage. No cracks over six hours later so I'm crossing my fingers that nothing cracks. Obviously there was no time for any acid. My wife and I mucked the bottom, shop-vac'ed the floor drain, and hit the water:

Best shot of the remaining staining. It's already beginning to disappear:
IMG_3647.jpg

A little distance is a beautiful thing. Stains actually fading, thanks to Mr. Sun:
IMG_3648.jpg

Gratuitous shot of the Guard Pup:
IMG_3655.jpg


Strainers are clean, and the light goes back in w/a little marine caulk before the water gets there. We'll test it tomorrow afternoon and set it straight for the weekend, maybe with a slightly high FC since we'll be away until Monday night. I want the house sitter to have nothing to do but feed the pups and break in the big screen. heh

Lemme know what you think. Man, I'm glad I took the day off. Glad my boss is a cool dude....gotta pack! Back in a bit.
 
One pic turned out to be all that was necessary:
IMG_3720.jpg


Not a crack to speak of, thank God. :bowdown: (Edit: No new crack. The one in the pic is from years ago.)

Due to us being gone on the weekend nothing was added after Friday evening, so zero chlorine shows up on the kit. I just added what the chart had for about 25000 of pool. pH is 7.8 so I figure I'll need to add a touch of acid. Researching that now, then on to CYA. If all goes well we'll be in the spa tonight! I'm really digging that 100XL kit btw.

Thanks again to all who helped. Back to the chemistry experiment!
 
Thanks much. I was in a real jam until coming here. This is quite a great site.

What's next is getting my CYA up (not registering yet, it's so low I'll have to boost chlorine, which is at 2ppm now) to keep my chlorine alive, and some scrubbing here and there. We're also going to get an umbrella for the spa since there's already a pipe stub right there. Then a cover, then....oh heck, I'll be busy. lol, at least I have the vac figured out and tested. This stuff is fun. Plus, with what I do for a living it's nice to get outside. I was quite relaxed after skimming and running the vac.

BTW the chems are fun to work with. I had someone puff up and proudly say "You don't want to do your own pool work. That's like having to take chemistry again! No way." My reply: "Um, that's what school is for. I took chemistry in HS/college so that I could do things like this myself." :cheers:
 

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