Strategy as I get started

[MoebiusStreet]

I'm just starting up a new pool - I've had water in it for a week now. It'll eventually be SWG, but it's not that time yet, we're still waiting for the plaster to cure. I just want to sanity-check my strategy for dealing with the water chemistry as we're getting it started.

We've got a floating chlorine dispenser full of trichlor pucks for the short term. I think that we're just waiting for this to dissolve to bring up the CYA level, which will in turn stabilize the FC. At the moment CYA is still very low, less than 20, and FC is just at 0.6. But I don't think there's any point in worrying about this at the moment, just let the tablets dissolve.

In the meantime I've been watching the TA and pH. The TA is around 150, so I'm trying to bring that down. I've been leaving the waterfall running to keep the pH rising, so I can keep adding muriatic acid. Each day the pH goes up to 8.0, and I add enough acid to bring it to 7.5, which (I think) will get me to a TA around 80 in a week or two.

In other news, my CH is only at 170, and I've got iron and copper each at about 0.5. I know I'll need to add calcium carbonate to bring up the CH, and I should probably sequester the metals as well. But I thought I'd leave that until the rest of the chemistry is all squared away.

With the amount of dust that was initially coming off the plaster, I'm surprised that the filter hasn't gotten at all clogged. In fact, with the pump running full blast, the pressure is only about 9psi. I'm guessing this is because the builder put in an oversized filter (or that's what he tells me). And by the way, I'm seeing far less plaster dust than I did initially, but how long should I expect it to continue (with quartzite finish plaster)?

Is my approach here correct?

 

[jblizzle]

Sounds like you have a pretty good grasp of everything

I would be a little nervous relying on the pucks for enough FC, but with the low CYA level, you might be fine. Safest would be to add stabilizer to get to around 30-50ppm right away, keep pucks floating if you want since you will need the higher CYA eventually, and then supplement adequate FC with bleach until you can fire up the SWG.

I would suggest getting the sequestrant in the pool soon than later ... you do not want staining to start already.

 

[JasonLion]

When starting up fresh plaster using one 7 or 8 oz trichlor tablet for each 10,000 gallons and leaving the pump on 24/7 generally takes care of the chlorine level quite well. Also, CYA and acid are needed anyway so things work out well. This approach is good for about three or four weeks, at which point it starts to be worth switching to an approach more in line with our normal recommendations.

With fresh plaster I wouldn't worry about TA very much. You are going to be adding acid regularly anyway, which normally keeps TA under control. You can also lower PH to 7.2 each time during the first three/four weeks. That will also help keep TA under control and give you just a little more head room on the PH increases.

It is best not to adjust CH during this initial period, as CH will be rising as the plaster cures. Raising CH now might cause it to be too high once the CH increase from curing plaster is over.

Plaster dust is most intense during the first week, though you often see some additional dust until the end of the first month.