To drain or not to drain?

[KCumings]

Our filter (Pentair DE 60) base cracked at the end of last summer. We finally got a new one, so you can imagine what the water looks like now (plus we have always had an issue with fighting black algae). We have had to SLAM it evey spring for the last few years (mostly do to neglect on our part).
Anyway, it’s a swamp now. I’m looking for recommendations on whether or not we should drain it and start over or SLAM it. I’ve read & heard some about a pool cracking if it is drained. I also would like thoughts on whether or not we should use the old grids (not in great shape) until it is mostly clean.

 

[duraleigh]

Welcome to the forum

You would need to SLAM even if you drained it. Perhaps a shorter SLAM but a SLAM nevertheless.

SLAMming a DE pool is a little more time consuming than sand. I would suggest you start the SLAM and bypass the filter for the first 24 hours and I would then suggest you use the old grids.

Please read "The "ABC's of Pool Water Chemistry" up in Pool School

 

[PoolGate]

That is a pretty large pool to drain I also would suggest trying to salvage the water. With the right help (TF-100 test kit and this site) you can bring it back and keep it clean.

 

[KCumings]

Will draining help quicken the SLAM process? And I guess my biggest concern is any solids from the algae but that just requires scooping with the net right?

 

[peirek]

Hi KC and welcome to TFP. The greatest site for the Average knowledge self maintainer.

You will want to remove all solids before starting your SLAM. Do you have a TFP recommended test kit (K2006 or TF-100)? Do you know your CYA level? You will need to know your CYA level and have a FAS/DPD test capabilities before you can begin your SLAM. Be sure to get your pH to around 7.2 prior to the SLAM. Turn off the SWG. A trip to Walmart to pickup 20-30 gallons of Great Value bleach (no additives - scent, easy pour) will be another step you will need to take to start the SLAM. Carefully follow the SLAM process and you will not need to drain the pool. It will take dedicated focus the first few of days to maintain the correct FC levels.


------ EDIT --------
Pictures are food for TFP'ers and will help assist you with your SLAM.

 

[DeanP66]

It really depends on that CYA number. If it is really high (90+), then a partial drain (at least 50%) is recommended. If it's 60 or below, you can just SLAM away.

 

[cfherrman]

Scoop out solids with net/rake, vacuum to waste till floor is clean, top up water

 

[Dirk]

I leave the pool chemistry and slamming to the experts, but I usually chime in when there's talk of emptying a pool. Doing so is not without risks, and can potentially damage your plaster. The older the plaster, the higher the risk. If I could do what needed to be done without replacing the water, I would, absolutely. If I had to replace water to get the water balanced, I'd replace as little as possible. Exhaust everything you can before you drain a pool, I say...

 

[KCumings]

Thanks for the input all. It's very helpful. The hubby was gung ho and thought it might be easier to drain. I got the test kit last year and the SLAM went well. Started skimming the chunks of Algae today (whew, what a mess). So, we can run the filter without the grids to start off with? I will check the CYA and pH in the morning. Our pH is always been high (I have since learned here due to the SWG). I don't think I quite understand the Ammonia thing though? I will go back over that part of the SLAM. I don't recall that from last year.
We were able to get it back into shape with the SLAM last year. I'm sure we can do it again. Another big concern I am researching and have researched before is the probable clogged skimmer we have (there are two) but I can post that in another forum. I'll post some pictures of the process.