alk dosing; trying to adjust for 2 or 4 day test....but

[atitagain]

i have some 5-6 pieces of various SPS in my tank that are all growing pretty fast in my opinion. The just "woke-up" about a 4 weeks ago after sitting dormant with growth for 2-3 after QT.

Ive been trying to get to a point where I can raise my alk to my preferred level of 8dkh to start my 2-4 day consumption test but I cannot raise it enough to start the test. It drops to 6.5, I spend 2-3 days trying to raise it .5 a day and then test after those 2-3 days and is test at 6.8-7. I use a hanna and salifert to verify. I know it's using the alk as I am dosing it over the 2-3 days trying to raise it. I've read to not raise more than .5 a day so how do I get it to 8 so I can calculate a 2-4 day consumption?

The tank is only using alk right now. I figure it's using about 3-4ml a day of red sea part B. I am dosing Kalk and the Calcium is holding solid along with mag.

Salt is red sea blue bucket, 4 gallons a week in a 30G JBJ rimless.

[Potatohead]

Just keep doing what you are doing and let it raise slowly to where you want but it sounds like you're chasing numbers if things are going well. Going from 6.5 - 7.5 or so I would personally want to do that over like a two week span.

[atitagain]

Originally Posted by Potatohead

Just keep doing what you are doing and let it raise slowly to where you want but it sounds like you're chasing numbers if things are going well. Going from 6.5 - 7.5 or so I would personally want to do that over like a two week span.

i am trying to do it slow, it just seems that slow isn't keeping up with demand/consumption. Admittedly I have been out of town a little recently but the wife had been dosing per my instructions. I didn't add for a day because I was waiting a day to test assuming it would be close to 8 and it tested at 6.8 instead. That would mean it's using roughly 1dkh a day assuming I got it to 8 but i don't want to assume that. I tested a few minutes ago and got 6.8, I will add 5ml of part B everyday for 3 days and then test again. I am just trying to figure out the daily dosing amount is all. I am not in the habit of chasing a certain number, just trying to calculate daily demand/dose to keep it near 8.

[Potatohead]

If you're using 1 dkh then that is the way it is, you will have to dose more. I've heard of tank with a lot of hard corals and coralline using three times that... It's all a good sign though since it means your stuff is growing. If you're using more than about .3 or .4 though you will probably want to move to dosing pumps as they can dose many times a day and keep your alk much more stable.

[atitagain]

Originally Posted by Potatohead

If you're using 1 dkh then that is the way it is, you will have to dose more. I've heard of tank with a lot of hard corals and coralline using three times that... It's all a good sign though since it means your stuff is growing. If you're using more than about .3 or .4 though you will probably want to move to dosing pumps as they can dose many times a day and keep your alk much more stable.

i will dose .5 for 3 days and test again and report back.

[bertoni]

Many tanks will consume 2-3 dKH per day. You probably just need to dose a lot more. 0.5 dKH per day is a very low consumption rate.

[RobZilla04]

Another option would be to switch to a salt with a higher Alk value. IO typically will measure near 11dkh @ 1.026 salinity. Perhaps a WC or two at 10%-15% each spread over a week will give you the boost you need without risking over dosing quickly.

[bertoni]

If the tank is dropping 0.5 dKH or more per day, water changes are going to be a very expensive way to go, and daily changes probably would be required. A 10% change would raise the dKH about 0.4 units, given 11 dKH for the salt and 7 dKH for the tank. A daily 15% change would be the minimum.

[RobZilla04]

I was suggesting water changes in addition to the dosing. Would that be raising the Alk too much too fast?

[bertoni]

I see. I think that you'd need to be careful about the rate of change, and that water changes are a very expensive and tedious way to add calcium and alkalinity.

[bdsage]

Originally Posted by bertoni

If the tank is dropping 0.5 dKH or more per day, water changes are going to be a very expensive way to go, and daily changes probably would be required. A 10% change would raise the dKH about 0.4 units, given 11 dKH for the salt and 7 dKH for the tank. A daily 15% change would be the minimum.

can you please explain how to do the math when my water change dkh is different from my tank water dkh including a % scale...? is there a calculator some where?

[bertoni]

For that computation, I was assuming that the tank was at 7 dKH, and the IO was at 11. So the difference in dKH levels was 4. Therefore, a 100% change would cause a 4 dKH change. A 10% change would do 10% of that, or 0.4 dKH.

[bdsage]

wow that was easy enough thanks

[bertoni]

You're welcome!

[atitagain]

I did a two day test and calculated that my tank is using .3dkh a day. Started at 6.7, added .5 for two day and ended at 7.1. So I will add .6 for three days and then daily dose .3 in the morning. I will do this and then retest after 4 days.

[bertoni]

That sounds like a good plan. Hopefully, you'll be able to back off on the testing fairly quickly.