Murky water

[Alphapapaoscar]

Hi all. I'm new to this site so please forgive me if this has been asked before.
My wife and I have just spent a fortune on a hot tub and we love it.
The water got murky after a couple of weeks so we drained it and started again.
The water was lovely and clear for a week or so so we chucked in some more shock and have started using chlorine tabs instead of bromine.
We have put in loads of shock over the last 3 days and 4 chlorine tabs so far but it's not even registering on the test strips.
Is this normal?
The murkiness is starting to clear very gradually but I'm surprised at the sheer amount we've put in so far in order for it to clear.
The hot tub is a marquis one and it holds (I think) 1500ltr

Any good advice will be appreciated.

Thanks

[mpkelley20]

Before you switched from bromine to chlorine you changed the water, right?  You can go from chlorine to bromine without issue but pretty sure you need to drain and refill before going to chlorine from bromine.

As far as chlorine, what type are you putting in?  Dichlor, Trichlor, other?  Some chlorine like calcium hypo does not contain any stabilizer so if you are running zero stabilizer then the chlorine will break down very fast.  Using Dichlor will add stabilizer so it will remain in the tub longer. 

Also, what are your test numbers for PH and Alkalinity?  If it is cloudy only after a few days, then something is out of balance.  Could be your source water that has stuff in it that you need to address.  Doing a simple test on PH, AL and maybe metals should give you an idea of what is out of balance.  Cloudy water can be a sign of high PH or Alkalinity so getting those in line would be a good first step.  PH around 7.4 and 7.8 and Alkalinity anywhere from 50 to 100 is generally acceptable.

Finally, how long are you running your filter cycles for?  Too short and your water can get cloudy due to lack of circulation.  I have a smaller Marquis (the Promise) which is 350 gallons and I run mine about 4 hours a day plus whatever it needs to run to maintain temps.  Does your Marquis have the spa frog system?  They make a chlorine based cartridge for that rather than bromine if you want to give that a try. 


Edit**  Ditch the test strips and buy a better testing kit like the Taylor one that uses regents.  Much more reliable

[The Wizard of Spas]

If they are chlorine tabs it is either Tri-Chlor or Calcium-based, as Di-Chlor cannot be tabletized.  I thoroughly recommend *against* chlorine tablets as they create a gas build-up that is not only noxious and hazardous to your health, it also chews away at the underside of your cover, allowing it to take on water faster and causing it to be replaced sooner.  Additionally- Tri-Chlors will lower your pH faster and more frequently.

I'd switch to granulated Di-Chlor if you're going the chlorine route.  The first 4 months of water chemistry is the hardest (your water tends to last 4 months before you need to drain it).  If you're always running low on chlorine, you're simply not adding enough.  Test 3-5x/week if you're trying to establish how much chlorine you need.  Once you get your equilibrium, you can throttle down to 1-3x/week for testing, based upon how often you use it.

Remember:  Test prior to entering tub, and add chlorine after you get out.  Next time you test, if you're low, you added too little and up your dosage (and vice versa).

I hope this helps.  Good luck moving forward.