Drain and add water at the same time?

Aug 7, 2013
32
Long Island, NY
Wondering if I can drain and add water at the same time. Just seems to make more sense time wise. I fear that my CYA levels are very high but don't have the test kit yet (ordered a Taylor kit from here). I've been using trichlor fast dissolve pucks since we had the 15 x 30 AG, 48" high pool installed last August. At the beginning of the season I was able to put two 1oz pucks in at night and wake up to a 2.0 a 3.0 reading. Now I've brought it up to 4 pucks and I'm lucky to have a 1.0 FC reading in the morning. At one point, a couple of weeks ago, my pH dipped to 6.8, although I understand that it could have been lower than that considering the test kit I have only goes down that low. I added a pH increaser and brought it back up and everything seemed ok but now not so much. I know I'm going to have to drain and add, but when I do can I do both at once?
 
Hi, welcome to TFP! It is possible to drain and refill at the same time. How it works is you put plastic tarp on the water's surface, and set up a pump to drain from the bottom of the pool. While that pump is draining you have a hose running on top of the tarp to add water at the same time. The pump will probably draw water out faster than the hose will put it in, so you will need to keep an eye on things and make sure you don't pump out the fresh water too! You can stop the pump and give the hose time to catch up when needed.
 
Thank you. I'll talk to my pool partner (my husband) so we can figure out what our best course of action is. This sounds like a good idea considering that if you do partial draining then add water and then do more partial draining and adding more water, you would probably be getting rid of some of the fresh water as well. My winter pool cover should suffice?
 
Since the refill water will likely be 15 degrees colder, you could probably have as much success by siphoning from close to the top at one end and the refilling from the bottom of the other end. The temp differential will keep fresh water loss pretty low.

If you use the tarp, the refill cold water will want to sink so the tarp will have to cover pretty well as it descends into the pool.

Either way, you can adjust your refill water to match the siphon so the overall water level remains constant.
 
The tarp needs to be over-sized and able to float on the surface of the water and most winter covers are fixed in place. You can read more about the procedure here, although in this case the poster was mucking out a pool as well.
 
I have pool pump. Would it be advisable to hang it over the side so that it is drawing the water from the top, or should I just do a plain hose siphon? Also, I'm assuming that the filter should NOT not be running. And lastly, if I'm not using the tarp, how would I regulate the water going out with the water going in?
 
If you can pump to waste you can use the pool pump. You would set it up like you were going to vacuum the pool manually. Have the filter set to waste, and let the head of the vacuum rest in the deepest part of the pool. On the opposite side have a hose gently add water at the surface. This will minimize mixing the "fresh" and "old" water while you drain and refill.
 
Betty99 said:
Not sure what you mean by having the filter set to waste. We have a cartridge filter. Is that why I'm not getting it?

Please add your pool details to your signature and location to your profile as described HERE as then we would have known you had a cartridge filter.
 

Enjoying this content?

Support TFP with a donation.

Give Support
BTW my pool is crystal clear. Not sure if I'm just lucky or if it's being helped along by the Aquafinesse I have been using after opening our pool to a bad case of white water mold. Also wanted to add that my pH has been holding steady at 7.2 for the past week :)
 
These are my readings from this morning. FC 2.0, CC 2.0, pH 7.2, TA 100. Here's the thing, I've had to increase the amount of chlorine to achieve this reading. As I have written, I started with 2 trichlor fast tabs. When we had the couple of weeks in the high 90s I increased to 3 tabs after seeing a very slight cloudiness on the bottom of the pool. This seemed to help but then my pH went down to 6.8 and it got more cloudy. I brought it up to somewhere between a 7.8 and 8.2 with a pH increaser. I then shocked and it cleared things up. Now the pH has been slowly going down again. I just feel that it's only a matter of time before I will have to drain. I am waiting for my Taylor kit. It should be here tomorrow, so then I'll now my CYA reading. Then I could figure out how much bleach I would need to maintain my pool because I'm not going to use the trichlor anymore.
 
A CC's test result of 2.0 indicates a need to SLAM the pool.

That said, we have no idea if that test result is accurate enough to rely on so you need to get your K-2006.

Continued used of tri-chlor tabs and the aquafinesse (whatever that stuff is) is not helping you....only driving your pH down and your CYA even higher (towards unmanageable) and you don't know how high it is now apparently.

read "The ABC's of Pool Water Chemistry" up in Pool School. That should give you a good beginning towards understanding the FC/CYA relationship which is likely the root cause of your issues.
 
Does your poolmaster kit differentiate between free chlorine and combined chlorine? I'm thinking you are getting the terms mixed.

Free chlorine (FC) is what does your sanitation/algae prevention, and combined chlorine (CC) is the normal result of that.

If in fact your CC is 2.0, that is an indicator that there is an algae bloom trying to happen.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.