Biofilm???

[snackcakegirl]

I bought my hot tub close to a year and a half ago.  It is located at our cabin and we try to go there every 2-3 weeks.  For this reason our dealer gave us a chlorine floater.  I realize this voided my warranty but I was told this was the way to go if we weren't going to be there to use dichlor, etc.

The first 8 months I had clear, beautiful water...decent readings and no issues.  We didn't use it much so my dealer said we could get away with draining it every 8 months or so due to low bather load.

I drained the spa and refilled it according to the manual.  Twice we let folks use our cabin and our spa.  I tried to tell them how to adjust the chemicals and use the test strips, but who knows if they did it correctly.  About a month and a half ago I opened the cover to find green water and a musty smell.  I shocked the hell out of the spa and opened up the floater to disperse as much chlorine as possible.  We had to leave but when we came back two weeks later, the water was crystal clear but our strips didn't read chlorine.  I went to my dealer Saturday and she said I need to dump the water because we most likely have a chlorine resistant bacteria...my strips worked fine in her showroom.

So I started to dump it and called her.  She said she didn't realize I was going to dump it that day and that I should have bought some cleaner to clean the plumbing.  I wish she had told me that when I was in the showroom.  So I used diluted bleach to clean the shell and the jets, let it sun dry and then I refilled it.  I followed the chemical instructions and opened my floater.  When I tested the following AM, everything was great except my chlorine read barely 3ppm.  I also saw a brown bubbly foam form in one corner of the spa when the jets run full blast.  I do have to add calcium increaser so maybe it is a mineral thing separate from a bacteria thing.

I can't believe I may have to dump my tub again because I have some biofilm thing going on...not to mention the fact I sat my butt in bacteria yesterday because the water looked fabulous.

We are in a drought as well in GA...so the thought of wasting more water kills me.  Does this sound like I have a biofilm issue?  What else can I do as an owner of a spa who only uses it every couple weeks?  I am literally sick over this.  

Thanks.

[TubsAndCues]

Well, here's the good news - it doesn't sound like biofilm to me.  Biofilm is a matrix of microbial cells that grow in the equipment areas and lines of pools and spas.  Typically, the only time you'll see a problem with biofilm is when you are using a biguanide system like Soft Soak or Baquaspa.  Chlorine and bromine, unlike the previous stated systems, do attack and kill biofilm as is recognizes it as an unwelcome guest.

Here's the bad news, but maybe not as bad as you thought - things still build up in the lines of spas, so I recommend using something like Spa Purge once a year to clean the lines out.  Do it next time you're planning on draining and refilling, the stuff is wonderful.

As far as not being able to maintain a chlorine reading, there are a number of things that could be happening.  One is that chlorine dissipates very rapidly in hot water.  Typically after adding chlorine, there will be only a minimal amount left 24 hours later.  

Another possibility is phosphates, which are primarily introduced by cleaning reagents not meant for pools and spas.  You'll generally notice an inability to maintain a proper level of calcium hardness in your spa as well.

One other thing is that high levels of chlorine can give you false results on your test strips by bleaching out the color strip.  

My personal recommendation is shock with a high level of chlorine and keep going with your routine.  Better yet (and here is where I'm in the minority on this forum), switch to bromine.  You can use the tablets the same as the chlorine tablets, and you don't have to drain and refill to switch.  I would, however, recommend getting a new floater if you do so.  Bromine and chlorine in their dry forms can have explosive results - literally.  It's extremely unlikely, but better safe than sorry.  

Hope this helps, at least as a start.

[In Canada eh]

snackcakegirl

Biofilms can form when someone is using chlorine, it happens all the time in drinking water mains.  The good news is that biofilms are organic and can be "killed off" with chlorine.  My advise would be to raise your chlorine level to 25 ppm and hold it there for 24 hours, you may have to test it a couple of times in that period.  Once you see no drop in the chlorine residual you should be all set.  You could either drain and fill then or buy a chlorine neutralizer to eliminate the high level

tubsandcues may be right, bromine could be a easier alternative for your application

[TubsAndCues]

Canada has a point, I didn't mean to imply that nothing can grow in a chlorine system.  That's why I recommend doing the Spa Purge once a year.  I completely agree to adding a large amount of chlorine, however you may not be able to maintain the 25 ppm he recommended.  Chlorine will begin oxidation at 10 ppm if your current level is low to non existent.  

What I should have clarified is that BioGuard and SpaGuard dealers like myself refer to biofilm as a specific type of growth that is a food source for pink slime/red algae.

Sorry if there was confusion.

[Vinny]

First, I want to say that I think your dealer lead you the wrong way. Anytime there is a question as to use chlorine or bromine the bromine will win out in situations like yours where the usage is minimal.

Second, using trichlor which is what you're probably use will raise your CYA and 8 months is a long time in a tub ... your cya was probably close to 1000 and your chlorine isn't doing very much.

Third, you may have a biofilm but using chlorinated water with high CYA won't do much of anything. You should disinfect the tub but you need to get to zero CYA first. Then use a pipe cleaner such as swirl away or something similar.

You probably should drain the tub, hit the tub with chlorine (could use bleach) to 50 or 100 PPM and make sure ALL surfaces are cleaned. Turn every diverter valve, air valve and anything else that can have water going through it, run the pumps for about an hour and drain the tub, fill again run the pipe cleaner and then drain. I know you mentioned you're in a drought but this is what is needed to clean the tub; you may leave off the pipe cleaner part as it may or may not clean the tub any more then the chlorine.

Get rid of the trichlor which was wrong to begin with and get bromine tablets, you'll need a new feeder as Trichlor can have explosive results if mixed with other chemicals. You also need to buy sodium bromide to start the tub up for a reserve and then adjust the bromine dispenser for the correct amount of bromine.

Using broine vs chlorine is probably going to be the best solution as you're not building CYA, bromine tabs may last a while (2 weeks or so) and it seems the perferred way to treat tubs that aren't being looked at on a daily basis.

[snackcakegirl]

Thanks everyone for providing such detailed responses.  I am happy to hear it is most likely not a biofilm issue, but I am upset that my dealer led me the wrong way.  I will switch to bromine next time I am up there and get a new floater.  I still don't know which method I will use to clean the tub...it makes me sick to have to drain and refill, potentially twice to rectify this situation.  I only have 2 days at a time when I am up there, so the time constraint is an issue as well.

Stupid question...what is CYA and what do I do to control it?  I use Trichlor tablets for sanitizer, MSP Shock, PH/Alk up (I have to add a TON of this to get good TA readings), PH/Alk Down, Calcium increaser, Stain/Scale defense and Defoamer.  Do one of these chemicals control CYA or have I been doing this all wrong from the start?  I read it is the stabilizer but I am not sure how this all works.  I follow my user manual for chemicals and there is no other chemical it says to use.

My strips measure Bromine, Chlorine, Alk, PH and Calcium.  All looked great when I left Sunday except my Chlorine reading was barely 3ppm.

[Vinny]

CYA is stabilizer which is in both dichlor and trichlor. There is no way to control it other than using chlorine without CYA (lithium) in it (the chlorine in the bromine tabs doesn't have CYA in it I believe) or dump and refill.

All of us who use dichlor chlorine ( the "perferrred" chlorine) run about 300 PPM in the 3 to 4 months we have our water in our tubs.

[windsurfdog]

...PH/Alk up (I have to add a TON of this to get good TA readings...

Though I am a dedicated dichlor user, I believe the advice you've received re: switching to bromine is very good..that, too, is what I would do considering your spa usage.  Should you switch to bromine, you probably won't have to add a "TON" of pH/TA increaser either as trichlor is much more acidic (pH 2. than either dichlor (which is pH neutral, 7.0) and bromine.