The Black Plague


New member
Jul 23, 2015
High Point/NC
I'm new to the forum and a relatively new pool owner. We bought our house in early 2015 with a pool/swamp containing several dead chipmunks and a bull frog bigger then my head. The plaster was flaking off in some areas and hadn't been kept up in about 1.5 to 2 years. We had it chipped out and replastered and replaced all of the floor returns/drains as the PVC was dry and crunchy. After several months of running a 3 hp non programable fixed speed pump, we replaced it with the intelliflo vs (huge energy savings).

As new pool owners, we asked the pool replaster guy how to take care of the pool. He pretty much said to drop a chlorine tablet in each skimmer and replace once it was just about dissolved, buy a test kit and go from there. The chlorine level was always a bit low on tests, but it always looked great, last summer we noticed a few black spots on the bottom and apparently they multiplied over the winter.

I've done some reading here and it looks like the best course of action might be the SLAM method with lots of scrubbing with a stainless brush during the process.

Here are the pool test readings as of this afternoon:

FC 0 (was 4 the night before)
ph 7.2 (added 1 gallon muriatic last night)
TA 40 (added 24 lbs baking soda today)
CH 300 (added 7 lbs calcium chloride today)
CYA 40

My test kit is a Taylor I believe, blue plastic box and I've been using Clorox brand Chlorine tablets which I believe have Trichlor.

2 Questions:
-People say to stock up on bleach before a SLAM, does that mean 20 gallons, 50 or more?
-I have a gas pressure washer, could I use this to remove the black spots while the pool is still full?

Thanks for any advice,



TFP Guide
Apr 15, 2016
Central Florida
Taylor Technologies 81329 Chlorine FAS-DPD Service Test Kit <--- is it this one?

or one of these:
Taylor Technologies K-2005 DPD Complete Chlorine Kit

Taylor Technologies K-2005-C Service Complete DPD Test Kit

Taylor Technologies 18571 DPD Basic Test Kit

Unless it is the top one, please consider ordering a standalone FAS-DPD test kit like this one for $30

Some pool stores sell the components of that kit, but often ends up being more expensive and not as fresh. One way or another, the "FAS-DPD" is what we're looking for, not just "DPD"

"drop a chlorine tablet in each skimmer" don't do that anymore, leave what's in there in there, but don't add for now please, they raise CYA too, see pool school

maybe 8-14 gallons depending on how much of an inconvenience it would be to go back to store....definitely don't buy more than 20 for now, try to store in shade

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