[Randy1]

Where should I try to run my PH & Alkalinity in my reef? I'm using Sea-Test Fast Test kit. After doing a 10% water change I noticed my Alkalinity at 3.5 MEQ./L the directions says this is a little high and I should proceed with an experiment my aerating some water and re-testing to see if carbon Dioxide is accumulating.

Thoughts

Thanks
Randy

[golfish]

Randy,
IMO, your Alk is about mid range. I think the most improtant thing is to keep it steady. I've ran my tanks a lot higher then 3.5 but not much lower.

[kevinpo]

PH of 7.8-8.4 is an acceptable range for most corals. I prefer to keep alkalinity just slightly above NSW. 2.9 - 3.2 meq/L.

HTH,
Kevin

[Arctic Fox]

hey, while we're at it? What is too high for alk? I just tested mine and it was about 16dKH in one of my tanks, and 12 in my other tank.

[Randy1]

?? my test kit says anything over 2.5 Meq./L you should collect a small amount of water and aerate for several hours and re-test. If this level is lower then you may have a CO2 problem developing.

[kevinpo]

IMO alkalinity over 4.0 meq/L is too high for long term system stability. Usually it is an indicator that calcium and/or magnesium is low.

If you have a buildup of carbon dioxide it will show up in your PH levels. CO2 reacts with the carbonates in the water forming carbonic acid which drops the PH. This is why hobbists who run calcium reactors without kalk additions tend to have PH on the low side. Generally around 7.8 - 7.9 rather than the 8.1 - 8.4 others have.

Regards,
Kevin

[Reefland]

Originally Posted by Arctic Fox

hey, while we're at it? What is too high for alk? I just tested mine and it was about 16dKH in one of my tanks, and 12 in my other tank.

Your readings are in dkH as where they are talking about meq/L.

[Arctic Fox]

Originally Posted by Reefland

Your readings are in dkH as where they are talking about meq/L.

I realize that, but even converted to meq/L my readings are still over 5 for Alk.

My Calcium generally stays between 450 and 600, (while one time, when I accidently dropped a container of Kalk in mind you, my readings shot up to nearly 1000 ppm)

pH stays around 8.0 or 8.1

anyone know of a good Magnesium test? I've never tested that

[cheeks69]

I realize that, but even converted to meq/L my readings are still over 5 for Alk....My Calcium generally stays between 450 and 600,

Which salt mix are you using ? For it to stay at those levels without precipitation then you Mag levels must be high also.

[Randy1]

reef crystals. I don't test for Mag.

[kevinpo]

I use the Salifert test kit. I try to keep my magnesium at 1325-1350ppm.

Regards,
Kevin

[Randy1]

Do need to add Mag.. often? What happens if Mag. levels fall too low?

Thanks

[kevinpo]

Every system is different depending on the bio-load. I add magnesium once a week but I have an unusual amount of stony corals.

Low magnesium can make calcium/buffer levels hard to mantain at the right levels. It also can cause calcium to plate-out on pump impellers, reducing their output and shortening their life.

Regards,
Kevin

[BubbaWPB]

As with most additions, it is best to test the levels if you're adding it. If you add kalkwasser for your calcium/alkalinity, you'll probably need to supplement your magnesium. How much? How often? It depends on your tank's uptake.