My test results not the same as Leslie's. What do I believe?

[Kathyteach53]

For TA numbers Leslie's is always lower than mine. What should I believe? I was getting numbers of over 200 closer to 300 with the 4 way test...fresh cemicals.Their readings were 240 and saying I only needed to bring down to 200. My readings were 300 and have brought down (with MA)to 210 and then brought ph up with Borax. I want an acurate reading with CYA and am afraid Leslie's readings (1st 40, then 45 then 35) are inaccurate. What sould I do next?
33k inground pool vinyl liner
Chlorinator off because of fear of extra CYa adding to pool
sand filter
Chlorine .5
ph 7.0 by rising.........not finished with borax treatment
CYA latest 35
Any ideas?
Clear blue (after adding agua pure--after Leslie's had me add 14#, all at once of soda ash ) has never been cloudy, other than the soda ash14# and no algae
Also, can't get Chlorine level up.
Thanks for any ideas...............Pool temp at 82 with solar cover in Ohio

[Buggsw]

Is your 4 way a test strip or drops? Strips are not very good.

Actually, I find my local Leslie's is pretty good compared to other pool stores. However, keep in mind that a sample that has sat for even 15 to 30 minutes can change the chemistry a little bit. Anything over 30 minutes the chemistry has definately changed some and anything over an hour - forget about having it tested. Especially if it's sitting in a hot car while you run other errands.

The area of the pool you take your sample from can vary in chemistry.
Whether you took the sample while your water was circulating or while your water was still can vary your chemistry. Always take your sample at the deepest part of your pool about a foot away from the edge and about a foot underneath. I invert the sample bottle so nothing from the top water get's in and when I have reached as far down and out as I can, then I turn the bottle on it's side to let the water get into the bottle. Try to stay away from a return and from a skimmer.

If your pool pump is running, the area near the skimmer is probably the worst chemistry while the area near a return should be the cleanest water.

Difference in the time of day, weather conditions, etc. All can vary the readings.

Actually, Leslie's doesn't seem too far off of your readings.

If you have a good test kit with fresh re-agents, you are always better off doing your own testing for the most common tests. Things like metals or other oddities, I take it to a pool store. So get yourself a good test kit that you can test your own CYA. Try to test at the same time/s of day and in the same location and chart your readings, noting the pool temp as well as time of day and all your various readings.

Pretty soon, you'll know what I call the "personality" of your pool and it's chemistry.