chemistry question: what's likely to change?

[Sk8r]

Question: When I do succeed in raising alkalinity to 2.97 in a tank with high mg and cal, will other readings start to change rapidly, and if they do, what should I grab first?
---a believer in belt and suspenders.

Parameters:
52 gal, skimmer, sump, 250 MH, actinic
Temp: 76.8
Alk: 2.19
Mg: 1500
Cal: 480
Water change: 5 gal yesterday. Tank age: 2 mos.

I added 2 tsp buffer to raise the alkalinity. In a week of testing, everything is rock-solid-stable, with 2 additions of 2 tsp buffer, water change, and just now, 2 more tsp.

 

[reedman]

As you raise your Alk your Ca and Mg will start to drop. But that is a good thing as your Ca and Mg are artificially high right now. Bring it up slow, the others will balance to a lower level just as slow. Water wants to be in balance.

 

[Sk8r]

Thanks very much for the reply---I'm trying to do this at the rate the buffer recommends: 2 tsp to 50-60 gallons. I'm watching the corals and fish behavior for any signs of problems, and will proceed with a small dose of buffer daily, then, with no further water change.

 

[reedman]

You can still do water changes (and I am an advocate of them if you don't have a HUGE tank). All you have to do is test your water change water to see what the Alk, Ca, and Mg are at and buffer it to match your tank water.

 

[mojoreef]

Whats your salinity at??


Mike

 

[Sk8r]

Oops, sorry: salinity 1.024.
I can't find my ph meter since the move.

 

[kevinpo]

Hello,
With your calcium and magnesium being so high I would bring the alkalinity up to about 3.5 meq/L so it will be closer to ionic balance with the other parameters. Then just wait for them to drop together. I target these numbers in my tanks:

Calcium 400-420ppm
Magnesium 1200-1260ppm
Alkalinity 2.90-3.20 meq/L

Regards,
Kevin

 

[Sk8r]

Thanks! Will do!

 

[Sk8r]

Just an update: adding 2 tsp buffer a day has produced:
Day 1: cal 490, mg 1500, alk 2.17
Day 2: cal ?, mg 1500, alk 2.86
Day 3: cal 450, mg 1470, alk 2.75
Added two more. Fish are happier, corals ecstatic, shrimp and other inverts are more active and I have snail eggs all over.

 

[reedman]

nice! always good to see a happy ending like this. Good job!

 

[Sk8r]

Thanks

I'm grateful for the help. So is my tank.