how high can i keep alk?

[wasp9166]

hi randy,
did a search but couldnt find an answer to my specific question,......... as long as i keep calcium in the 380-450 range , how high can i bring my alk in order to help keep ph up? and at what point on the ph scale should i worry about bringing it down( altho this probably wont be a problem till spring :rolleyes: ) as always thanx............

[Randy Holmes-Farley]

I wouldn't raise pH above about 8.5 unless you have a specific reason for wanting to do so. If it is for dinos, then maybe a little higher is OK. As to alkalinity, it is unlikely that alkalinity itself will cause a big boost in pH if you are alredy in the 8.4+ range. Adding high pH alkalinity supplements will have a bigger effect. I'd say that short term you can push 11-14 dKH if you want to.

[wasp9166]

i know, it helps tho , 8.5 is out of my league , im trying to maintain 8.1 right now , lol..............what do you mean by short term? i guess i should rephrase..............how high can i safely keep my alk in order to help ph for the winter? if i keep an eye on ph at what point should i worry about lowering it back down? it was 4.5 meq at one point b4 i had all this precipitation take place, is that pretty much the limit?

[Randy Holmes-Farley]

Trying to simultaneously keep high pH and high alkalinity will result in a lot of precipitation of CaCO3 and possibly low calcium (if you are not using balanced additives). How high you can push them depends on how often you want to add more additive, and how often you want to clean your pumps.

If you use a balanced additive (which is what I suggest), then you will not be in complete control of how high you raise them. Precipitation will be the limiting factor. I think that is what you found with the limewater.

[wasp9166]

ahh , i do use bionic, i thought by just dosing the alk part i could get alk up a bit then continue with both parts........i had noticed with a bit higher alk my ph was a bit higher, just trying to get every little bit i can, ill go back to using both parts

[Randy Holmes-Farley]

i thought by just dosing the alk part i could get alk up a bit then continue with both parts........

Yes, that will get the alkalinity up, at least temporarily. But if you keep on that way, calcium will get depleted.

[wasp9166]

yes i understand..............so 4.5 is about it then i would think, thanx

[Randy Holmes-Farley]

If you are also pushing pH, that might be near the high end, yes. If the pH were lower (7.8), then the max alkalinity could be a lot higher.

[wasp9166]

ok , with 4.5 i get about 8.1s, thanx

[Randy Holmes-Farley]

You're welcome.

Good luck!