Filling up pool for the 1st time

[kimkats]

@Dirk nailed it again! Each pool and environment is different so you need to find what works for yours. Once you find it it will be a breeze to keep doing!

 

[ellislo]

@Dirk @kimkats will SLAM again. Will try to maintain higher FC than the one indicated in the chart

 

[ellislo]

Almost done with my 2nd slam. I read somewhere that to maintain FC at 15%-20% of CYA before further dropping down FC to recommended level. What is the reason for this?

I had algae outbreak after a few weeks from my 1st slam previously by having CYA 70 and FC 6. So I am thinking of maintaining higher FC for my pool this time, say FC 8-9

What do you guys think?

 

[kimkats]

I would shoot for the higher FC for sure. For the next week or so keep it just under SLAM level. Then bring it down and keep it at the top end for your CYA for now on. Better safe than sorry so you can enjoy your pool!

 

[ellislo]

I am using cal-Hypo, i know it will add CH to my pool, but i can only get trichlor & cal-hypo locally, can't get liquid chlorine. Was using trichlor previously for chlorination until CYA getting to 70, then switch over to SWG. I bought cal-hypo previously when i did my fisrt SLAM.

I am now going into the 3rd week of my 2nd SLAM. Initially when i started the SLAM, i can see green/brown powdery stuff on the floor, since a week ago, there was no more green/brownish dead algae on the floor, instead, grey color powdery stuff (dead algae?) can be seen when brushing.

I started SLAM with CYA at 70 and trying to maintain FC at 28. My CH has also raised to 300 when tested today. When i tested the CYA, it has became almost zero (I tested twice to be sure). I am using LaMotte TesTabs Cyanuric Acid Tablet and just noticed the expiry date is 11/20, will this be the main problem? I read that CYA can degrade with temperature at 90F (32C), which we are having over here in M'sia all year round. But i never experience such a drastic drop previously.

So now what should i do?
1. Assuming CYA is zero. Chlorinate using Trichlor tablet to bring CYA to 30 and maintain FC at 12 for SLAM. Switch back to cal-hypo once CYA reach 30. However, i need to be wary of my CH not to raise more than 400.
2. Drain/refill pool for half of the water to lower CH and restart SLAM just in case i need more cal-hypo dosing to complete the SLAM, as i do not want to be caught in the situation where CH reaches 400 and i am still in SLAM.

 

[ellislo]

Dead algae or fine silt?

 

[kimkats]

Use a turkey baster and suck some up. Put a white paper towel in a strainer and squirt the water out onto the paper towel. Let it dry and take a pic of it once it is dry.

 

[ellislo]

This morning, I noticed there are more of these stuffs on the floor, an mostly along the seams. I believe these are dead algae?

 

[ellislo]

The stuff completely dried up. Greyish in color Abd powdery when I touched it.

 

[kimkats]

Since there is no greenish/yellowish color to it I am leaning to dirt/dust from the air. It might be dead algae as well and just need to vacuum it up as you can and filter it out of the water. The glass media in your filter might not be able to catch to very well so you might want to over fill your pool and vacuum to waste to get it out.

 

[ellislo]

I am willing to replace my glass media with sand media if it does provide better filtration. Wouldn’t want to vacuum to waste so frequently…..

 

[kimkats]

THere are some people who like the glass but most that have it switch to sand after a couple/few years. You can switch to sand and add some DE to the sand to help it filter even better.

 

[ellislo]

I have decided to refill my pool rather pouring more chlorine and testing to the pool, since it is much more cheaper to just refill.

Refilled was completed on 18 May. I have since chlorinated the pool with 3kg trichlor tablet, which should have provided 30ppm CYA to the pool water. Have been running my pool for the pass few days with SWG. Based on my observation, daily FC lost to UV is 3.5, so I am running my SWG (1.58 lbs/d) 6.5hr-7hr daily, which manage to maintain the FC level at 8ppm. I am reluctant to further raise my CYA to 70ppm as recommended, as it will require high FC for SLAM if i encounter algae outbreak again. I suppose there shouldn't be any issue for me to have FC at 8ppm, since it is still well below the SLAM level.

Thinking back at what had happened previously, i think the main mistake that i have made that caused algae outbreak was that i operated/chlorinated the pool alternate between SWG/trichlor constantly but still keeping the FC level around 5 (FC target for SWG pool). I supposed i should have follow the target FC for non-SWG pool, which is around 8-10, since i was not fully on SWG.

 

[ellislo]

My refilled was completed on 18 May, and I have been maintaining my cya around 40-50 and FC around 9.5 or more, the brownish dirt/dead algae issue came back last week .