Alkalinity too high

[KBzreef]

Two weeks ago my pH meter went on the fritz. But before I realized it was not working properly I put in a boatload of pH buffer to bring the pH up. Then realized the meter was fried. I did a 20% water change on my 120 gal. reef tank to get rid of some of the buffer. The buffer brought my pH up too high to 8.8 and I had to add seltzer water to bring it down. My alkalinity has been 20-21 dKH every since.

Then I added a calcium reactor to stablize the calcium.

Today my problems are: Alkalinity 21 dKH and does not seem to be moving my calcium is 420 ppm. My pH has been running 8.5 day and 8.2 night. I'd like to get the pH more stable around 8.2.

The calcium has been stable at 400 - 420 ppm for about 1 week and the pH same time.

Also, I don't know if it is related but I lost 2 cleaner shrimp in the last two days - are they sensitive to alkalinity?

?How can I get the alkalinity down to the recommend 7-10 dKH? Can high alklanity harm my fish or corals?

[bertoni]

I doubt that the alkalinity harmed the shrimp, but it's possible. If you're worried, some water changes are the only safe way to lower alkalinity.

pH buffers almost always cause problems, since they are just high-pH alkalinity supplements. They are not a good approach to low pH problems. This article might help:

http://reefkeeping.com/issues/2004-09/rhf/index.htm

[KBzreef]

Thanks for the response. What time frame needs to go between each water change? How many gallons can be changed and how frequent can I do that?

[bertoni]

I wouldn't do more than 20% at one shot, probably around 15g, and twice a day is the highest frequency I'd try. One per day is likely enough, and there's no need for more changes once the animals are looking better. The tank might not need any changes at all.

[Europa13]

Never try to adjust your pH. Buffers only cause problems. pH is only affected by carbon dioxide and alkalinity. Make sure you have good flow in your tank and maintain your alkalinity and don't worry about the pH. There is a DIY baking soda recipe to raise alkalinity, once it is within range, you can use a daily 2 part calium/alkalinity additive like ESV B-ionic to maintain the levels.

Alkalinity drops fast on it's own and that is why a daily additive is necessary if you don't drip kalk or have a calcium reactor. Since your alk is very high, I would just do a few water changes and let it drop on it's own. Don't add any additives until it has dropped.

[KBzreef]

Thanks for all the responses. I am going to go home and do a 20% water change and try to bring down the Alk.

[bertoni]

You're welcome! Good luck!

[KBzreef]

I did 3 water changes - total of 90 gal. each 24 hours apart. After the first two I did not see a difference and decided to turn off the calcium reactor. With the third water change the Alk went down to 17 dKH. calcium is at 400 ppm. I am planning to do another 30 gal water change tuesday which will be 48 hours since the last one.

I took my green horn coral to the LFS because it seem to be suffering from tissue necrosis. They said it could be having an adverse effect to the high ALK. It is in their stable tank now. What do you think? The bottom of the green stalks have turned white while the tips are still green.

[bertoni]

People have reported problems like that with high alkalinity. I'd leave the coral there until the tank is back into the normal range.