Can't raise ALK

[Adamc1303]

So I have been recently having an issue with my alkalinity. I have a 300 gallon system and I am using a calcium reactor with a kalk reactor to keep the PH up. My tank is pretty well stocks with sps. Recently I tested my Calcium, Magnesium and Alkalinity. I usually just test my alkalinity. I noticed that my calcium was very low. This was probably due to me dialing in my calcium reactor just focusing on DKH. I guess every time the DKH tested low I added baking soda but never any calcium. I accidentally raised my calcium level too much which I guess doesn't really affect anything. It got up to prob 550. It was to high for an Elos and APT test kit to detect. I also raised the MG to 1300. I would like to raise it a little more. The main issue is that my alkalinity keeps dropping. I keep gradually raising it with baking soda hoping it will hold and it just doesn't. I doubled my effluent rate and lowered the co2 controller to keep the reactor PH at 6.45 to 6.55. I am using a hanna meter for alkalinity testing. The only thing I recently changed on my tank was that I added VHO lighting and also did a 5% water change using tropic Marine Pro instead of seachem reef salt. I do adjut the reactor allor because I tend to keep stocking the tank with more and more sps. the colors are a little dulled out lately which I think has to do with the low calcium and dkh levels. It went down from 7.56 to 6.16 in 24 hours!


Thanks,

Adam

 

[jdezek]

I've been battling low alk also but I'm not running any reactors or dosers. I tried dosing alk products but got nothing. Mine stayed around a 5.2 - 6.2 then I tried baking soda in my top off water and now it maintains around 7.4. I put 1 table spoon in 2 gals of RO/DI and that usually last a day to a day and a half. Might try dosing baking soda regular like that see how it works.

 

[reeftivo]

What's your specific gravity reading?
When I've had issues, it was lower than 1.025.

 

[Adamc1303]

It may have dipped to 1024. I usually keep it at 1026

 

[bertoni]

I'm not sure how much alkalinity the reactor is producing. You could try turning it up, but I might shut it off for a bit and dose by hand, to see what might be happening. If you measure and dose alkalinity at the same time every day for a while, you should be able to get a good estimate of the actual alkalinity consumption rate. Calcium kits are less useful because there's too much noise for this purpose. I'd likely use a 2-part, and dose equal amounts, but since the calcium level still is high, I might just skip that supplement for a bit.

I'd also get a second opinion on the alkalinity test kit.

 

[Adamc1303]

Thanks for the reply.

It dropped to 6.5 from 7.0 again today. I raised with baking soda and now have the calcium reactor effluent line fully open. The only other adjustment I can do is lower the ph in the reactor even more Right now it's between 6.45 and 6.55 which I think is pretty low. How does getting a bigger reactor help? Do they have bigger inlets and outlets so they get more water through the reactor and delivered to the tank?it' a 300 gallon system and I am running a

Super Reef Octopus® 8” Calcium Reactor
Dimensions: 16.5”x11”x23”
Features the new Water Blaster HY5000W
High quality machine welded cast acrylic construction
High performance design
Rated for a 400gal tank

It holds 3 containers of the large arm media. I also have a second chamber that has a little media in it and then zeo mag. I recently added the 2nd chamber with the zeo mag. Could something be happening in that chamber causing the effluent to be lower in alkalinity? Could it be getting consumed in there before it even makes it to my sump?

 

[bertoni]

I don't know enough about calcium reactors to help much there. The second chamber should be fine. I don't think it should cause any precipitation. That seems very unlikely, but you could try removing it.

Have you seen any signs of precipitation, like buildup on the heater or maybe near the output of the calcium reactor?

 

[Adamc1303]

no signs at all

 

[bertoni]

Okay, I wouldn't worry much just yet. I suspect that the calcium reactor just can't keep up with the demand. Unfortunately, I have no idea what, in reality.

 

[Adamc1303]

I am starting to realize that this is probably the issue. May be time for a new reactor!