Alk WC issues

Evan West · Feb 16, 2017

So I posted a thred a while back and I had a big alk drop from 11-12 down to 7-8 and since it has stabilised there and ive had no problems. Went to test the water for my WC today and it mixed to 10, what should I do? I need a WC but I dont want a large swing again. its a 5g change in a 20g system

Diesel · Feb 16, 2017

Do only a 1 gallon change now and 1 gallon tomorrow and a 1 gallon on Saturday, that should be enough.
How long are you between water changes?

Evan West · Feb 16, 2017

Diesel said:
Do only a 1 gallon change now and 1 gallon tomorrow and a 1 gallon on Saturday, that should be enough.
How long are you between water changes?

usually a week but i was so busy last week i put it off

Diesel · Feb 16, 2017

How come your ALK is dropping from 11-12 to 8-7 with in a week?
You have a heavy bioload on SPS corals?

Evan West · Feb 16, 2017

Diesel said:
How come your ALK is dropping from 11-12 to 8-7 with in a week?
You have a heavy bioload on SPS corals?

No that was a previous issue that has passed, currently im dropping from 10 to 7-8 in 2 weeks. Usually i do weekly changes so the large drop is not a problem.

Sabellafella · Feb 16, 2017

Evan West said:
So I posted a thred a while back and I had a big alk drop from 11-12 down to 7-8 and since it has stabilised there and ive had no problems. Went to test the water for my WC today and it mixed to 10, what should I do? I need a WC but I dont want a large swing again. its a 5g change in a 20g system

If your alk is 8. And your water change water is 10 dkh. A 5 gallon water change on a 20 gallon system should only raise it by .5dkh witch imo isnt an issue. Its about the same swing i get from weekly 20% water changes

Diesel · Feb 16, 2017

Evan West said:
No that was a previous issue that has passed, currently im dropping from 10 to 7-8 in 2 weeks. Usually i do weekly changes so the large drop is not a problem.

That is still a big drop just for two weeks.

Randy Holmes-Farley · Feb 17, 2017

Diesel said:
That is still a big drop just for two weeks.

Huh?

You mean it is undesirable? It is certainly not an unusual amount of demand.

Alk demand is typical 1-4 dKH per day in a reef tank. he only dropped 2-3 dKH in 2 weeks!

Diesel · Feb 17, 2017

Randy Holmes-Farley said:
Huh?

You mean it is undesirable? It is certainly not an unusual amount of demand.

Alk demand is typical 1-4 dKH per day in a reef tank. he only dropped 2-3 dKH in 2 weeks!

That might be right but we don't know what corals he has.
In my DT that I had close to 80 large SPS colonies my ALK dropped if not dosed only 1.5 DKH and I tested many times.
Now that I got rid of the SPS colonies and have only a bunch of LPS I had to turn my CaRx off as my ALK spiked close to 13 and for three months, I didn't dose and just did on a 200 gallon tank a 10 gallon WC once in the three weeks and my ALK over a period of 3 months dropped to 7.
Now I dump once a week 100ml of ALK and 40 ml of both CAL and MAG in the DT to maintain a 7.5 DKH.
Yes I know numbers don't add up but I can't put it any other way.

Evan West · Feb 17, 2017

I currently have 5 Euphorically colonies, a blasto colony, mushrooms, zoa, acans, a plate coral and a favia colony. I had a 2 dKH drop in 2 weeks so 1 a week, the only problem is that i didnt want a 2dKH jump in a single day with a WC

Staggs · Feb 17, 2017

Thanks for posting this. I just started dosing staying around 8.5 dKH, but I haven't done a water change yet. Typically do 10G water change on 85G and my salt is typically right around 8 dKH. so I was wondering what I'd need to do when i do a WC.

Sabellafella · Feb 17, 2017

Staggs said:
Thanks for posting this. I just started dosing staying around 8.5 dKH, but I haven't done a water change yet. Typically do 10G water change on 85G and my salt is typically right around 8 dKH. so I was wondering what I'd need to do when i do a WC.

If your salt is lower in alk, just dose the makeup Water to get it up to snuff. Imo, its not necessary. As long as your salt mix is in the same ballpark as your tanks parameters, and arent doing over a 50% water change. You should be fine

Randy Holmes-Farley · Feb 17, 2017

Staggs said:
Thanks for posting this. I just started dosing staying around 8.5 dKH, but I haven't done a water change yet. Typically do 10G water change on 85G and my salt is typically right around 8 dKH. so I was wondering what I'd need to do when i do a WC.

Dose, as suggested, or do nothing. You'll never notice the difference with a 10-15% water change.