Baking Soda/KH Question

Roan Art

Roan Art

AC Members
Oct 7, 2005
5,387
0
0
65
Northern VA
bowheads.org
Still waiting for my pressurized CO2 tanks to get here. Grumble.

My tap water KH has dropped to 2 and that means my new 75g is usually sitting at 1 KH and 7.6 pH. The coral is taking forever to dissolve and bring up the KH readings to a safe zone.

Assuming my tanks get here soon, would it be prudent to temporarily add baking soda to raise the KH to a safer level so that I can begin injection? Once the CO2 lowers the pH enough for the coral to dissolve more rapidly, it should correct itself, right?

If I added baking soda:
1) How long would it take to raise the KH?
2) How much should I add for 75g?
3) How long does it last (roughly) until I need to add more?

I don't like adding stuff to my tank, so if I have an general idea of how long it would take to raise the KH, I can plan accordingly.

Thank you
Roan
 
Baking soda is powerfull and very fast. For me one teaspoon of Arm and Hammer raised 30 gallons of water 1 dKH. It did so about as fast as I could swish it around good. It isn't a bad option to use (with caution) I just switched over to the CaCO3 method largely because it made no sense to add Baking soda for Kh and then add Calcium via some other form. I needed the calcium. It would be fine for raising your Kh to start things off. Once added it is there until something consumes it (bacteria) or you remove via water change. It is as stable as any method available.
Dave
 
How much coral are you using? Seems like it's been at least a couple of weeks since you started using it, right? If so, it should start having an affect if there's enough of it.
As Dave says above, Baking Soda will do the job quickly, but not last long in the tank at all, so if you don't have your 3.0 - 3.5 and you want to inject you'll have to use it on a temporary basis.
You may have to add a bunch more of the coral for it to be affective, so an answer to my first question would help.

Len
 
I think the key to the coral situation is the pH. coral does not dissolve well once the pH reaches 7.6. As soon as she starts adding co2 the coral will take over and buffer the tank. Until then baking soda would be the way to go.

In reality a tank with crushed coral and co2 injection is a calcium reactor. It is also a carbonate reactor. The fuinny thing (Or the thing I don't fully understnd) is that once you get the Kh raised in the water it will remain there even when the pH goes very high.
In other wordss CaCo3 won't dissolve at or above pH 7.6 which at atmospheric co2 is somewhere in the 1.5-3 range on KH But if we drive down Ph and dissolve the CaCO3 we can get KH much higher. then we remove the co2, and the pH jumps through the roof. but the KH stays in solution.
Dave
 
One teaspoon of baking soda per 10 gallons will raise your kH by 4 dH. I use it sometimes to buffer my tank whenever my water starts drifting into the realm of acid water since my water supply is moderately soft. Calcium Carbonate does the same thing but also raises your GH.
 
daveedka said:
. . .In reality a tank with crushed coral and co2 injection is a calcium reactor. It is also a carbonate reactor. The fuinny thing (Or the thing I don't fully understnd) is that once you get the Kh raised in the water it will remain there even when the pH goes very high.
Click to expand...
Yes! I noticed that and I was going to ask about it. When the bottle on the bowfront runs low and my pH climbs back up to 7.4-7.6, my KH is stable at 4 dkh and doesn't drop below it. That's great stuff, but I'd like to know why, too :)

Roan
 
djlen said:
How much coral are you using? Seems like it's been at least a couple of weeks since you started using it, right? If so, it should start having an affect if there's enough of it.
Click to expand...
Len,
This is one of my new 75g tanks that I set up on Christmas Day, not the first one everyone was helping me with :)

When I was doing the first tank, my KH out of the tap was 3 so I was able to inject right away. Now the tap KH is 2 and the new tank is 1, so it's not safe to inject without some aid.

I moved my coral filled Magnum from the bowfront to this tank, but the pH is 7.6. I just put more coral in the baskets of the Emperor last night, so that should help. If need be I'll throw socks full of coral in the water tonight :)

I'm going to end up with a reef tank at this rate :)

Roan
 
Most excellent!

Dave, Len, rrkss: thank you VERY much for all your help. Soon as the tanks get here and I'm ready to inject I'll add the soda, check the KH, and start injecting. I'll also continute to monitor on a daily -- or twice daily basis if need be -- until everything is under control.

Thank you again,

Roan
 
'.........I'm going to end up with a reef tank at this rate......'
No you won't. Don't be afraid to jack up the quantity. Coral is very slow acting so when you start to see a difference you can start removing it bit by bit, making sure that there's still enough there to hold the buffer.
There are people on this forum with kH of 7, 8°H and higher and the fish are fine. And coral won't raise the kH that rapidly for concern on your part.
And if you can go fishless for a bit in that tank, all the better.

Len
 
'.........I'm going to end up with a reef tank at this rate......'
No you won't. Don't be afraid to jack up the quantity. Coral is very slow acting so when you start to see a difference you can start removing it bit by bit, making sure that there's still enough there to hold the buffer.
There are people on this forum with kH of 7, 8°H and higher and the fish are fine. And coral won't raise the kH that rapidly for concern on your part.
Click to expand...

This is very true.
Water changes with lower Kh tap will generally help keep steady levels as well. Since I do large chages weekly, and my tap is a few degrees below tank levels, It tends to balance out well with coral. I have a lot of coral in the syatem, and additionally have it mixed in the substrate of an RFUG not in the filter. I would surmise with my co2 levels and my location/quantity of coral it is dissolving about as fast as it can in a normall y run tank.
Fair warning Aragonite is much much more rapid than coral. If you mix or change you will see different effects in the speed of changes. I made the mistake of switching to aragonite and not testing properly. My KH jumped to a nice solid 11 Degrees in two weeks. Aragonite is great just be aware it has a far faster reaction than coral.
Dave
 
You must log in or register to reply here.
AquariaCentral.com
Top Bottom