Help With KH
 

I'm using a Salifert test kit and my KH is at 15. It came with a 7.5 check test and it tests at 8.0. I assumed that the kit was crap but after doing the test on the check bottle that came with it now I'm a little concerned. My KH has always been at this level. Everything else that I have tested for is good. Cal 420/MG1440/PH8.3/ sal 1.025 My parameters have been like this for 2 years. How is this possible without a meltdown? I'm running a calcium reactor with a bubble every 2 seconds and the effluent is a steady drip at 6.51. But according to the test kit it is at 7.3 Also a Kalk reactor that runs with my ATO. What do I do to bring it down? I also think my colors should be alot brighter, I think they are a little on the brownish side.

I dont think 15 dkh is high enough to cause a tank crash. I accidentally pushed my alkalinity up to 22 dkh once for several days and all I lost was one acropora.

I havent used salifert in the last two years. I didnt know they could test pH and came with a referance sample. I thought only Seachem did that?

To bring your alkalinity down just shut off your calcium reactor and kalkwasser reactor for a few days and it should come down quickly on its own. Test daily to make sure it doesnt drop too low. To speed up the process do a water change. When you start them up again you may want to lessen the flow through the reactor some more.

Another way you can check the accuracy of a test kit is to test some newly mixed saltwater. Your results should be similar to these http://reefcentral.com/forums/showthread.php?t=1714505

I will shut them both down for a bit. I had the same readings before I used both reactors which has me baffled. So keep the bubble count the same and turn down the effluent coming out? Growth is good and no nuisance algae and also, corraline growth is'nt like it used to be. Would this high alk have anything to do with my coral colors? A pink poccilopra I got from you is a wine color in my tank

Regardless of what the flow through is you want the internal pH at about 6.5 so turn down both appropriately. Coral color is mostly a product of lighting with overall water chemisty and feeding coming second in my opinion. Everyone has different opinions on what works it seems and I've seen beutiful colors with all methods so I dont know. Get your alkalinity down to the normal range and take it from there I guess.

So it turned off the kalk reactor and shut off my ph monitor for the calcium reactor. The effluent is still going. Well nothing has changed in the alk. Should I shut off the effluent? I also checked my test kit with some freshly mixed IO and it tested at what it is supposed to be at so the test kit is not the problem. What next? Should I be concerned with a kh of 15? It has been like this for 2 years. The old saying "if it aeint broke don't fix it" So is it broke?

Yes, 15dkh is too high and you should fix it...slowly You're overdosing on Ca/Alk. Shut off your Ca reactor and Kalk and monitor the alk daily. It will come down.

Shutting off the Ca reactor means stopping the flow through it completely. If you just reduce the flow, you might actually INCREASE the output of the reactor. Restart it once the tank Alk is down to 9 or so. Then check the alk the next day to see that it is staying at that level.

If the alk starts to rise again, you'll have to dial back that Ca reactor. Run it at higher pH.

Thanks guys. I turned it right off now. The calcium actually went up to 440.

Ok so got my kh down to 10 and have been maintaining that for about a 2 weeks with my calcium reactor back on line. Now my cal is at 360 and i'm running my mag a liitle high right now at 1500. I have yet to put my kalk reactor back on line. If I do will it bring up my calcium and make my alk to high again? My calcium reactor is set at 20 bubbles per minute and the effluent is at 40ml per minute. Any suggestions on tweeking the calcium reactor?

Although SPS might not be hit hard by a single ALK swing with a ALK swing from 6-7 to 12-13 you will start loosing any zoa colonies you have in the tank. They are a great indicator to ALK changes for some reason.

Salifert is notoriously inaccurate with their KH kits regardless of that little bottle of calibration solution. They seem fairly reliable for calcium, and their magnesium kits are pretty good. The Salifert KH kits generally test 2 dKH higher than actual KH level (compared to using a colorimeter, or Elos kit which is quite reliable for KH). So your KH is probably closer to 13 dKH than 15 dKH. Have you double checked your techniques? A friend of mine thought he was at 15 dKH, but it turned out he was at 7.5 dKH because he was using the quick method of the test where you use half the drops.

It sounds like you just purchased this Salifert kit, how do you know that your KH has always been at this level? Have you been testing it using other methods? Are you simply assuming that alkalinity has been at 15 (or 13?) dKH this whole time? If so, it is possible to not have a meltdown simply because it has always been at that level. Critters are resilient, and steady numbers are less detrimental than abstract numbers.

Turn off both calcium and kalk reactors, manually dose just calcium to keep it at your normal level until the alkalinity drops to be in the 7's (in the 9's by the salifert kit). As alkalinity drops the calcium will go up (although your tank may use it up before you notice this, but be aware it may not take as much dosing of calcium as you may think). Once the calcium and alkalinity are balanced turn the reactors back on. You should be testing calcium and alkalinity at least on a bi-weekly basis to make sure the numbers aren't getting skewed as reactors aren't perfect. You should always have some powered calcium and alkalinity supplements on hand to supplement when the numbers have gone out of balance.