Alkalinity drop in 3 days?

ethankap · Oct 22, 2017

Wednesday I tested my tank and it was at around 8dkh (using Red Sea's kit, which is 1dkh accurate).

It's a 45 gallon tank, about a month old. I added a Goby and torch yesterday, did a water change today. The alkalinity is now 7dkh.

My LFS said its too early to need to dose or test calcium or mag. Should I worry about this drop? I'm not dosing anything at the moment.

Nitrates are at 2.5ppm after the water change today. Phosphates at 0.0. PH 8.2

jda · Oct 22, 2017

It could be a testing error, but if it continues to move downward, then you need to account for it.

ethankap · Oct 22, 2017

I should also note the Hanna test is showing phosphates at 0 but I have some good algae growth and everything seems healthy.

jda · Oct 22, 2017

You can have phosphates test at zero and have algae - the algae is using them up. Aragonite will bind phosphate too. Don't see a zero phosphate reading and think that you neither have any nor need to do water changes.

ethankap · Oct 22, 2017

jda said:
You can have phosphates test at zero and have algae - the algae is using them up. Aragonite will bind phosphate too. Don't see a zero phosphate reading and think that you neither have any nor need to do water changes.

I don’t. I do a 10% water change like clockwork every Saturday and clean the filter sponge. I usually stir up the substrate a bit before hand as advised.

Randy Holmes-Farley · Oct 23, 2017

Just monitor alkalinity (it is the canary in the coal mine for needing dosing) and if it drops any more, look to dose calcium and alkalinity, such as with a two part system.

ethankap · Oct 23, 2017

Randy Holmes-Farley said:
Just monitor alkalinity (it is the canary in the coal mine for needing dosing) and if it drops any more, look to dose calcium and alkalinity, such as with a two part system.

Thanks. Will monitor. Any advice on which two parter is good? Seachem? Or Red Sea's foundation A and B?

Randy Holmes-Farley · Oct 23, 2017

ethankap said:
Thanks. Will monitor. Any advice on which two parter is good? Seachem? Or Red Sea's foundation A and B?

I'd personally use a DIY (say, from BRS or other supplier of materials) or if you want to use a commercial one, I'd use ESV B-ionic or a different company that you trust.

For commercial two part systems, there's no independent data available on what exactly is in any them, aside from manufacturer claims of various sorts. So it all boils down to who do you trust. If there is a company you trust, I'd go with that company's two part.

ethankap · Oct 26, 2017

Update:

I bought the Hana calcium and alkalinity test.

Calcium is at 465ppm and alkalinity is at 7.9dkh. Nitrates (mid-week, water changes are on Sundays) is at 2.5ppm