is KH of 7.7 acceptable?

[naser]

my affleunt is at 14 but my tank is at 7.7... i just increased my bubble count so ill retest tommarrow.... but is 7.7 allright?

[newreefman1]

Natural seawater is just over 9dkh. YOures is acceptable but I would expect youres to be higher with a reactor. I keep mine around 11 dkh..YOu can certainly raise yours but remember if you just turn the bubbles up, you can also increase the amount of Co2 being released into your tank and cause the Ph to plummet if proper oxenygation isnt reached.

J

[Ninong]

Yes, 7.7dKH is acceptable but something a little higher would be even better. Natural seawater has an alkalinity of 6-7dKH (2.1-2.5mEq/L) but this is one of those parameters where it is safer to maintain a higher buffering capacity. Delbeek & Sprung in TRA-1 recommend maintaining reef tanks at 7-10dKH (2.5-3.5mEq/L) but most people recently are recommending 10-12dKH and 425-475ppm Calcium with pH of 8.2-8.4. If you can achieve those numbers you have reached the holy grail.

Ninong

[newreefman1]

Ninong, where did you get that Natural seawater is 6-7 dkh. I have always read just about 9?

J

[Ninong]

That's according to Delbeek & Sprung in TRA-1, p. 228, however it varies higher than 7dKH in some areas, although they don't mention that.

Ninong

P.S. -- Dr. Craig Bingman in his article on Calcium & Alkalinity gives a value at the lower end of that range for alkalinity in "typical seawater."

"Typical seawater has about 10 µM (400 mg./L) calcium ion present. The baseline alkalinity is approximately 2.0 mEq/L total carbonate alkalinity. All of these numbers are approximate and bounce around a bit depending on whose assay one takes as grail."

P.P.S. -- Fossa & Nilsen give a value of 8dKH as typical for natural seawater. So I guess it depends on where you get your sample.

[naser]

well the salifert test kit says seawater is 8dkh or alkalinity of 2.9. with reactor alone im having trouble reaching those goals... im constantly having to add calcuim to keep the alkalinity up.

[newreefman1]

I may miss the mark here,

but adding calcium shouldnt raise your alk and stabilize it....you should be using a buffer if you want to start to raise it without the help of the reactor. Otherwise, fine tuning the reactor and finding its Optimum levels for your tank will get you the alk that you desire.

I tweaked mine the second I got it and sat on the floor with it messing around for quite a long time. Im still slowly letting the tank adjust and increasing the bubble count extremely slowly.

J

[thezookeeper]

Anthony Calfo in The Book of Coral Propagation also marks the alk of seawater at 7dkh, but recommends higher levels in our closed systems for the same reason. FWIW, Calfo gives an excellent explanation of water chemistry and cause and effect in that book. HTH


Joanne

[newreefman1]

Naser,

I have that book and its great. Its the one I referenced yesterday actually. If you wanna borrow it..lemme know

J

[nudlnek]

Hey Ninong!!


You are the Holy Grail of reef keeping!!!!

[naser]

turns out i was only putting 3ml of water when the test kit wanted 4ml.... turns out my kh is at 10

[newreefman1]

lol

thats alot better