Crush Coral For Kh Increasing?

[nivisec]

Hello,

I have a 20 gallon tank that is heavily planted, but low light (and low light plants to match). The decay rate on these plants, because of the number of them, is causing my kH to be basically 0. 1 kH is as high as I can get it and it doesn't hold for more than 12 hours or so.

If I let my kH monitoring go, my pH will shoot to 5.0 within a week I'd say. It has happened before and I didn't catch it for some time, but thankfully having barbs mostly (and feeding them good) they weren't phased by it.

I'm keeping the pH in balance (around 6.8 for my barbs) by adding baking soda every day to bump up the kH enough to keep the pH stable for that day. I can't really keep adding baking soda to get kH higher because it would skyrocket my pH. So I'm at a dilemma. I don't want the baking soda to be a permanent solution and I really don't want to remove my plants.

I don't have a measurement of my GH right now, as I have no test kit for it. I know that I need to keep it on the softer side for my barbs though, so I'm also in a dilemma for that.

• I want the kH up to about 3-4 and the pH of 6.8.
• Would some form of crushed coral that I run water through be a solution here? I think crushed coral may raise the GH too high however, so any thoughts on this (yea, I really need to measure it, my friend has a test I'm going to get at work this coming week)?
• Does anyone know of anything that would be a more permanent solution of increasing kH only that I could put into my filter?

 

[GoldLenny]

Cuttlebone also works and you can manage it like you do with baking soda but without having to do daily dosing as it will slowly dissolve. You will have to adjust how much you add and how often to keep the KH where you want it.

What is your tap/source water baseline? See my blog on how to establish this. This would tell us more about what is happening once the water gets in your tank.

Do you have driftwood or other wood in the tank?

Are you doing proper filter maintenance? If you don't properly clean your filters on a regular basis, the decaying detritus will cause your KH to plummet. Also, at least lightly vacuuming your substrate to remove any excess detritus from the bottom also.

 

[rdd1952]

For a 20 gallon tank, you could add a small amount of crushed coral to your filter and solve the problem. You would probably only need a teaspoonful or maybe less. It shouldn't raise it too high but would keep everything in check. Also, if you are having that much problem with decaying plants, then something is wrong. You need to either remove some or get better lighting. It's also possible that you have plants that arent true aquatic plants. Anything with varigated leaves isn't suitable for an aquarium.

 

[nivisec]

@rdd1952
I guess I made it sound like I have a bunch of dieing plants, sorry about that I spend too much time on the fish tank every day, so they are all pretty much flourishing (minus a dwindling black brush algae problem being corrected, after almost pulling my hair out, thanks to users on this forum). There are also all low light species that I took my time in researching, so I'm 100% sure they are aquatic. However, I do have quite a few and they are constantly growing new leaves to replace dead ones that my dojo loach seems to to enjoy demolishing directly into the water every night before I can remove most of them.

Anyway, thank you for answering my crushed coral question. I would have added way too much on my own (tablespoon increments) I am setting up a brackish water tank in the future, so I'll have to buy some of it anyway, which is why I was curious to begin with.

@GoldLenny
I didn't know what Cuttlebone was until just now, but that is another cheap way it appears I'll have to check that out at the pet shop tomorrow. The crushed coral is way to expensive at the pet stores, so I have wait for it to be shipped to me and would like a better temporary solution. I try to support my local stores and all, but paying double for something there is where my desire to support them dwindles.

I have 2 pretty small pieces of drift wood in the tank (really just sticks I attached my java ferns to), but I didn't think it was big enough to cause any large change...Am I wrong? Also by sticks, I mean maybe 2.5 inches long on one and 3.5 on the other, both maybe 1/4" in diameter.

I've tried religiously cleaning the filter, vacuuming every day, and doing a 5-10% water change every day for like a week without luck. The pH and kH just plummet by the end of the next day. Currently I haven't done a water change in about a week and a half due to trying to keep my CO2 down and kill off the black brush algae. My nitrates are below 10ppm due to my plants.

Also, I read your blog just now and I really didn't have any idea you should drain the hot water tank to remove sediment...Doing that tomorrow, as I'm sure it hasn't been drained in at least a year since we bought the house. As for my tap water, I just tested it and it's pretty disappointing and may explain some stuff (see the stats below). I don't have a water softening system in the house to blame sadly. I had also tested my water before and remember getting a kH of 2, but that was during the winter time, so that could have affected it.

Cold Water

• pH 7.2
• Nitrates < 5ppm
• kH < 1

Hot Water

• pH 7.8
• Nitrates < 5ppm
• kH < 1

One would also think maybe my kH test isn't working, but I tried 2 different ones. I also get a good reading on my turtle tank and my betta tank. I buffered the turtle tank up with baking soda and it has stuck very easily (due to no plants I'm sure). The betta tank buffered itself up, by I'm assuming a sea shell my wife put in there. I do have a large clump of moss growing in the 5 gal betta tank also with no problems.

So, I guess I'm pretty much going to have to use some artificial buffer. I had no idea city water anywhere could be so soft right out of the tap.

 

[rdd1952]

Your KH test is most likely fine. Most municipal water supplies have 0 KH as they keep the alkalinity at a minimum to improve the taste of the water. Mine is that way. When I first got my test kit I thought I was doing something wrong. It said when you added a drop the water would turn blue and then would eventually turn yellow. It never turned blue but went straight to yellow meaning my KH was just like yours. As for the artificial buffer, the crushed coral will do that too.