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ItsMee
10/02/2009, 11:22 AM
I posted these questions in the no0b forum as well and realized I probably ahould have posted them here instead, so here they are:


My calcium has been at 360-380 ppm and my alk at 7-8 dkh. They are both on the low side. My tank is new and has been cycled for a good 3 weeks now and the clown fish in it is doing great (I put him in when the cycle was over). I do not have any corals and the only other life in my tank besides the clown is a bunch of live rock (it really helped cycle the tank fast). When the coralline algae started losing its color I began testing the calcium and alkalinity. I have decided to use limewater to control these parameters as well as PH. I have mixed 1 teaspoon of ms wages pickling lime per gallon of distilled water and I don't use any that is older than 2 days. The last 2 nights i dripped 16 ounces of kalk from a water bottle slowly as the top-off to hopefully raise calcium, and alkalinity a little. I measured calcium and alkalinity today and they have both not changed from their low values. My magnesium is at 1300.

My questions are:
1. is it safe to say that the 32 ounces (16 ounces at a time) I have dosed these 2 nights has not RAISED my calcium or alkalinity at all, but has merely MAINTAINED it since the values have not changed, or is 2 nights enough time for it to change?
2. My PH is at 8.2 and sometimes gets up to 8.4, is this swing dangerous, and what is the maximum swing that should occur?
3. Is it possible to raise the calcium and alkalinity slowly over time without having to dose a 2 part if the only thing using calcium in the tank is coralline algae?

anemone123
10/02/2009, 12:43 PM
First, with what you have in the tank, don't worry too much. I have had clownfish only tanks where I never checked the Calcium or Alk and they were even lower than yours and the fish were fine.

I am assuming you are wanting to get this tank "reef ready" for corals in the future and it sounds like you are taking it slow and making small changes. Since you drip the Kalk solution into the tank you can mix the solution a little stronger.

I don't know how to calculate the amount you will need to get back to acceptable range but your tank is really low so it will take some time.

For reference to someone that can make the calculations can you tell us your tank size?

anemone123
10/02/2009, 12:44 PM
Also the pH swing you are seeing is normal.

Billybeau1
10/02/2009, 12:46 PM
limewater will not raise cal and alk very much. It is used more to maintain the levels you already have.

You will need to use calcium chloride to raise calcium and baking soda to raise alkalinity.

There are commercial 2-parts available but they can get expensive if you have a big tank. There are diy products that you can make yourself. They are listed here

http://reefkeeping.com/issues/2006-02/rhf/index.php

Otherwise, if your tank is not too big, you can use Kent's Turbo Calcium or Seachems Reef Complete to raise calcium and good old Arm & Hammer baking soda to raise alkalinity.

This handy calculator will tell you how much to dose.

http://home.comcast.net/~jdieck1/chem_calc3.html (http://home.comcast.net/%7Ejdieck1/chem_calc3.html)

Good luck.

ItsMee
10/02/2009, 12:58 PM
You are right in saying I am getting my tank reef ready and taking it slow.

My tank is a cadlight 39G pro system: I used the volume calculator that is linked on Randy's dose calculator and everything considered (live rock, equipment, water line in sump/tank etc), my net volume is about 40 gallons. Actually it said 50 gallons, but I am saying it is 40 to be on the safe side :)

Are you absolutely positive you can not dose limewater in such a way that you are putting in more calcium and alkalinity per day that is being consumed thereby increasing these values daily?

Billybeau1
10/02/2009, 01:06 PM
I'm not saying you can't. The problem is you will need to dose so much that it may raise your pH more than you want it.

It all starts with the salt mix you use. If you use a salt mix high in calcium and alkalinity, then yes, limewater can maintain between water changes. But if you use a salt mix with low cal and alk out of the box, you will need to supplement anyways. Not to mention once you start adding corals and such as your demand is going to increase.

ItsMee
10/02/2009, 01:11 PM
How do you go about calculating how much your PH will be affected? BTW, thank you very much for taking the time to help me - I really appreciate it :)

anemone123
10/02/2009, 01:19 PM
If you want to maximize the system you could put a pH probe in the sump ran by a controller that controls a solenoid that will shut off your Kalk top-off if the pH gets to high.

Billybeau1
10/02/2009, 01:21 PM
Well, you really need an electronic pH meter like a Pinpoint. These are not that expensive and are worth the money IMO. Hobby grade titration type kits just can not give you the accuracy you need to monitor pH in the 10ths.

anemone123
10/02/2009, 01:27 PM
I think we are talking about three different problems.

1. How to get your current tank Cal/Alk to where it needs to be?

I agree that a two part solution will raise Cal/Alk the quickest but with the current load I would just start increasing Kalk until parameters get in line. It will take at least a month but if done slowly will cause no harm.

2. You need to measure your fresh saltwater because Instant Ocean is low in Cal/Alk. but you need to know whether you are raising or lowering parameters with water changes.

3. You need to measure the amount of Cal/Alk your tank used per day or week.

anemone123
10/02/2009, 01:29 PM
I second the Pinpoint and probe.

I also recomend Neptune controllers but they are more expensive.

Billybeau1
10/02/2009, 01:32 PM
The new Instant Ocean is not low in calcium anymore. It has never been low in alkalinity. Usually 12-13 dkh out of the box.

ItsMee
10/02/2009, 01:42 PM
I do use instant ocean and mix it to 1.025 SG per my refractometer . I use a ph/temp pen to measure ph, not a liquid test. it measures to the accuracy such as 8.39 (the highest I have seen it) and I have just calibrated it. I wanted to know about the PH because I kinda wanted to figure out how much kalk I can drip safely without making the PH go too high. I can not get a controller at the moment. I don't mind it taking a month to increase. If I do decide to add it with a 2 part supplement to make it go faster, are you supposed to add the alkalinity and calcium at the same time? Its obvious they can not drip near each other, but they do drip at the same time? Maybe I will buy an ionic calcium supplement and use baking soda. If I don;t bake it in the oven it will make the PH go DOWN...right? Well what if I drip kalk which will raise the PH a little, but at the same time drip small amounts of the 2 part additive that lowers the PH...would that be safe to do?

Billybeau1
10/02/2009, 01:54 PM
You may or may not see a slight drop in pH with un-baked baking soda. Either way, the drop is very temporary and should rebound quickly.

anemone123
10/02/2009, 01:56 PM
I cannont answer all of your questions because I don't use baking soda.

The poorman's anwer to your pH question is to start the Kalk drip in your sump. Then using your pH probe measure the the sump pH once an hour making sure the pH doesn't rise more than .2 and if it does then next time don't mix it as strong.

If the pH rises more than .2 it won't hurt your fish.

ItsMee
10/02/2009, 03:51 PM
Awesome, thanks for the info. I will start dripping kalk with twice the potency (2 teaspoons per gallon) tomorrow while measuring PH every hour and then go from there. I know every system is different, but how often should one expect to have to dose magnesium?

Billybeau1
10/03/2009, 06:11 AM
Magnesium depletes much slower then cal & alk. You may only need to test once a month or so and adjust from there.

ItsMee
10/05/2009, 01:46 PM
I have been studying Randy's articles and decided to use limewater as a means of a balanced ca and alk supplement. When I first tested, the calcium was at 340-360 ppm and alkalinity was around 7 dkh. I have no corals, but I do have a fair amount of coralline algae. I have never used any additives in this tank before (it is fairly new, but completely cycled). I decided to attempt to raise my calcium and alkalinity by adding more ca and alk via limewater per day than my coralline can consume thereby slowly increasing my levels to normal and to not use any other calcium or alkalinity additives other than limewater. I first started by replacing all my top-off water with 16 ounces a day with a concentration of 1 teaspon per gallon of water (I never use limewater older than 2 days). I test my ca and alk in the morning and at night with my PH readings. I noticed that since I drip this 16 ounces slowly at night that my PH readings do not change too much so just recently I bumped the concentration up to 2 teaspoons per gallon 16 ounces at a time.

My questions are: My calcium has increased to only 380 ppm while my alkalinity is now at 10 dkh - so my plans are working, but are these levels balanced? It seems that the calcium is a little on the low side (as I have heard is normal with Instant Ocean salt). I am new to this and would like to get it down pat before introducing any corals. I would like confirmation that what I am doing is correct and I would also like to know where I should go from here. Should I add 20 ppm of calcium and then continue the balanced limewater, or should I only continue the balanced limewater without worry of adding anything un-balanced? It seems as if the ca and alk demands are fairly low considering how ca & alk have increased with how little limewater I have added - which makes sense if the coralline is the only consumer? Once the ca and alk are at levels which are balanced and just need to be maintained, what is the best way of going about finding a good approximation of what I should dose daily to not increase these levels, but just maintain them?

Percula9
10/05/2009, 02:06 PM
You can't make the kalk stronger than it is, if the water is already saturated. The rest of the kalk will just precipitate to the bottom. You will need calcium chloride to raise the calcium.:wave:

bertoni
10/06/2009, 11:01 AM
Those numbers are fine, and I wouldn't worry. As long as alkalinity is in the range of 7-11 dKH and calcium is within 350 and 450 ppm, the system should be fine. If you want to increase calcium, some calcium chloride, such as Turbo Calcium, would be fine. The tank might get a bit more growth with a higher calcium level, but that's not clear.

ItsMee
10/06/2009, 12:05 PM
Awesome! so 360-380 ppm calcium is enough for corals and algae to use to grow, or it is it just enough to keep them from their growth being stunned?

Also, does anyone know what instant ocean's calcium level is supposed to be when it is freshly mixed...at what S.G.? I mix mine to 1.025, I just want to see if my batch has the right amount of calcium.

bertoni
10/06/2009, 12:13 PM
Corals and coralline will grow well with calcium at 360 ppm.

IO should be at 400 ppm and 11 dKH at 1.0264, and just a bit below that at 1.025