help. Question about shocking with Bleach

[catagory5]

It shows on the Pool Calculator to get a shock with my CYA level of 60-70 I need to add something like 7.5 gallons of 6% bleach. Can that be right? That is a whole lot of bleach. heck, that will cost me like 30 or 40 bucks. I do have 'some' algae spots around the pool, but nothing a little elbow grease wont take care of but I think it is time to shock. Anyway, I guess I need to go buy a whole hack of alot of bleach huh?


Thanks.

 

[waste]

Hey Cat5, yeah it seems like a lot! Unfortunately, as long as you plugged in the correct #s in the calculator, that's the way to do it. If you can find a source of 5 gallon carbouys of 12.5% , you may save quite a few $. Also, if you have a very mild bloom, it may only take a day or two shocking (combined with brushing and vacuuming) to clear up the problem I doubt you're looking at $30 worth of chlorine for this 8)

 

[Ohm_Boy]

Well, with a CYA level of 60-70, you need to reach AND HOLD an FC level of 24 - 28 or better to shock the pool. So, yeah... that's probably about right, depending upon how big your pool is and what the current FC level is. It might be worth looking at a partial drain/refill to lower the CYA.

Why don't you post a full set of numbers and pool specs to see if maybe there is something else going on. Maybe you could get away with using some Cal-Hypo to shock, depending on your calcium levels, which could save some bleach.

 

[catagory5]

FC has been running 3 to 4 TC is the same CC has been virtually 0
TA is 100
PH is 7.7
CH is 400
CYA is 70 last check.

I don't have an algae "bloom" per se, I am getting these little green dime size spots about the pool here and there. They are light greenish in color and with a brush can be almost brushed off if I get down in the pool with them. It isnt real bad but I want to stay on top of it. Anyway, my pool is sparkling and crystal clear so it aint all bad.

Thanks for the info.

 

[reebok]

your chlorine is way low for your cya level assuming you aren't using any other method to keep algae away.
pool-school/

 

[fuzzy_dba]

FC has been running 3 to 4...
CC has been virtually 0
TA is 100
PH is 7.7
CH is 400
CYA is 70 last check.
I don't have an algae "bloom" per se, I am getting these little green dime size spots about the pool here and there. They are light greenish in color and with a brush can be almost brushed off if I get down in the pool with them...

As much as I hate to say it, you are having an algae bloom .
With a CYA level of 70 your MINIMUM FC level should be 5-6 and your Targeted levels should be 8-9. Running a FC level of 3-4 is why you are getting algae; there's not enough chlorine in the pool.

There are 2 options:
1. Do the drain and fill routine to drop your CYA, then shock and keep the chlorine at the levels listed in Pool School: http://www.troublefreepool.com/pool-school/chlorine_cya_chart_shock
2. Keep your current CYA and raise to shock level of 28, maintain umtil the FC drops less than 1.0 in and overnight test.

 

[frustratedpoolmom]

I agree, consider lowering your CYA level - and then stock up at Wal-Mart or similar big box stores on their store brand bleach - it's cheaper, and you should be able to get it for less than $25...

Also look for 12.5% at pool stores, if you can get it for around $3 a gallon it's a good price.

 

[scubasteve]

That sounds very similar to what I was going through up until a couple weeks ago. My CYA was up around 80 to 90 and I was fighting a vicious battle with algae constantly. I backwashed, replaced water and shocked the doody outta my pool and all is well (a good water replacement gets your CYA down,that and stop using those pucks). My cya has been holding around 50ish, I have been using a reasonable amount of LC each day (2 gallons per week), not a single hint of algae in the pool. Bottom line, just having an elevated level of CYA is kinda like being on the brink of disaster, makes your pool unresponsive to regular maintenance. Get that CYA where it should be and everything else will fall in line too.

.....And I learned it all right here!

sS

 

[catagory5]

Actually I am using No More Problems Which is an algaecide. Last summer and the first part of this summer My water has always looked crystal clear. Only problem has been the spots here and there of the greenish dime sized whatever. aside from that it has been peachy. One reason I really hate to keep my Chlorine up around a 5 is because it dries out all of our skin so much and makes the hair feel like straw. But I know it is to keep alll the bugs out of the water. Your Darn if you do and Darn if you dont.

 

[waste]

Cat5, take a look at this post to see if you think borates might do your pool a favor

 

[duraleigh]

. One reason I really hate to keep my Chlorine up around a 5 is because it dries out all of our skin so much and makes the hair feel like straw. But I know it is to keep alll the bugs out of the water. Your Darn if you do and Darn if you dont.

I don't think in a properly chlorinated pool that is an issue. Too many members here on the forum run their FC around that level without the adverse effects you describe. Nevertheless, if you lowered your CYA to 30-40, you could run 3ppm FC if you would feel more comfortable.

RE: cost of chlorine to shock. I imagine the cost of the algaecide each year is more than the cost to shock your pool with chlorine. If you can get the algae out of your pool, you really have no need for algaecide. Few of us on the forum use it.