Can't get alkalinity up!

[Adamc1303]

I have been having a major issue keeping my alkalinity high. No matter what I do I lose 2 or more dkh daily. The tank is. 240 gallon reef tank. Its about 5 months old at this poimt. It's not heavily stocked with sps at all. My demand shouldn't be so great. My calcium level remains high at 440 or even over 500 at times and my magnesium level stays at the 1400 mark. My ph gets up to 8.15 at most and goes down to 7.9 at night. I originally had a very large octopus calcium reactor with a deletec Kalk reactor going, however I had to basically open the entire valve and get a stream out of the reactor to keep up and it was causing my ph to dip to below 7.7 even with the kalk coming from the top off. I now switched to a doser and I am dosing 250 ml of ESV 2 part daily and my alkalinity is still dropping. What's weird is that I didn't always have this issue. In fact I had a much heavier sps stock in my tank until they all rtn'd from all dropping and swinging while I adjusted. I had 65 ml per min of effluent coming out of the reactor and it would hold. All of a sudden about 6 weeks ago I started having this issue and can't seem to fix it. The only thing that I can think of that I changed on my system was adding a chiller since it started getting warmer. I also don't see any precipitation on heaters or pumps. The tank has no coralline growth due to this alkalinity problem. Please help me out if you have any ideas as to what can be happening.

Thanks,

Adam

[bnumair]

hi Adam
its very common for reef tanks to drop 2-3 dkh per day. all it means consumption in ur tank has gone higher due to coralline algae or coral growth. just need to up the doser.

[dunk373]

What are you trying to get too? What's the reading now and what kit are you testing with? What kit is the calcium? Are you adding equal amounts of two part? I use two part and alk was low I tried to raise it and it would drop right off. I added extra and when I finally got it higher the calcium was low so I decided that 7 was all I could get. Coral growth is still the same as when it was 10

[Adamc1303]

Thanks for the reply bnumair I always had calcium reactors and never dosers. How much do folks with 240 gallon tanks typically dose? Doesn't 250ml per day for a lightly stocked tank sound like allot? Bye I am still using kalk in a reactor for top off.

[Adamc1303]

What are you trying to get too? What's the reading now and what kit are you testing with? What kit is the calcium? Are you adding equal amounts of two part? I use two part and alk was low I tried to raise it and it would drop right off. I added extra and when I finally got it higher the calcium was low so I decided that 7 was all I could get. Coral growth is still the same as when it was 10

I tested with Red Sea and a Hanna tester. Btw off topic but everyone says Hanna testers are off but I didn't find that. Both test kits gave me very similar readings. I am trying to get to 9 dkh. I know I can keep it at 7.0 but right now it's not holding so it can drop to the 5's which it has a few times and I lost clams.

[dunk373]

Ok 5 is low. I dose 180 ml day and my tank is packed with sps that grow a lot so something is off. I really don't think size is much of a factor, a lot of surface area will eat it up with coralline growth. I did have some issues in the past trying to raise one or the other. Example I had 400 calc and 9 dkh I wanted calc to be 430 so I upped the dose by 15ml a day I rechecked in a week and now all was 8.5 calc 415 I left it and ck. a week later and calc was 430ish and alk 8. It always seemed to lower the other when you raise one. Maybe cut down on calcium and raise alk say 10ml on each

[bertoni]

According to this calculator:

http://reef.diesyst.com/chemcalc/chemcalc.html

assuming 180g of water, I get about a liter a day of B-Ionic alkalinity solution if the consumption is 3 dKH. I think that this is why the DIY formula and calcium reactors are fairly commonly used.

[Adamc1303]

That's basically where I think I need to be at. Almost a liter a day! Can there be anything else going on though?

[bertoni]

Yes, I'd check the surfaces of the heater and maybe inside a pump or two for signs of precipitation. On the other hand, I had tanks that went through 2-3 dKH per day just from coralline algae growth. There were no stony corals or clams in the tank.