Problem with spa start up

Oct 3, 2014
Los Alamos, NM
I recently bought a house with a J-335 hot tub, and am having trouble with the chlorine levels on start up.

Because the previous owners used the SoftSoak system, I superclorinated the spa yesterday to decontaminate it (to about 100ppm), let it run for 30 min, and then added Sea Klear spa flush and let it run for another 30 minutes before draining and refilling. Because I was running out of time and light, I then added about 1.5 tsp of dichlor which appeared to raise the chlorine levels to about 2-3 ppm, as expected. So far so good...

Today I got back to the tub and followed the start-up instructions for the Nature 2 + MPS system (I bought the startup kit from spa depot). The Alkalinity and pH seemed OK at first (though the pH is now coming in high, a problem I've not yet corrected). I added calcium to raise the hardness to about 150ppm and then added the Sea Klear Natural Clarifier (0.7oz) and Spa Choice Metal Free (9 fl oz). Finally, I added 1.5 tsp of dichlor as I had the night before (since I was no longer detecting any chlorine), but the levels did not appear to rise at all. Over the course of this evening, I'd let the pumps run for 20-30 min, check the levels, and add another teaspoon of dichlor, for a total of 6.5 tsp, but while this should have raised the levels to about 12 ppm, the test strips are only measuring about 1ppm.

The Metal Free bottle says that it may lower the chlorine levels in the spa, but should it neutralize this much chlorine, and continue to do so several hours after adding it to the tub? I need to get the chlorine levels up to 3-5 ppm before adding the Nature2 cartridge, but I don't want to overdo it if for some reason the true level isn't registering.

Any help would be greatly appreciated!

P.S. Before superclorinating the system, I raised the chlorine levels to 10ppm and about 14 hours later, they were still about as high, so I don't think there is excessive load on the system.


Mod Squad
LifeTime Supporter
TFP Expert
May 19, 2010
Tucson, AZ
Why are you adding all these things in the startup kit?

You started out on a good path, but now sounds like you are starting to add a bunch of things that are not needed.
Is there metal in your water? If not, then no need to add a sequestrant.
There is also certainly no need to be adding a clarifier either.

You also need to realize that we do not trust test results for test strips as they can be very unreliable and inaccurate.

I do not know anything about use of the Nature 2 and MPS in a spa. We generally do not recommend the Nature 2 in pools, but it is apparently a valid method for spas.

... OH, just realized that my comment about the metal is silly, since you are intentionally adding metal to the water with the Nature2.

Sorry, this is not turning out to be very helpful :D
Oct 3, 2014
Los Alamos, NM
So I'm following the start-up instructions that sent with the kit, which is why I'm surprised that I'm having trouble with the levels.

I tried again tonight by adding 1 tsp (no change) and a second tsp (finally, a small increase to about 1-2 ppm, but not the increase I should be seeing).