Alk question - some general guidance please….

[TheXpander]

Hi all,

I have a 40 g sumpless system running a canister filter.
The canister is mostly filled with Matrix and has some floss for general waste capture.
I’ve recently upgraded from FOWLR to starting with some corals, upgraded the lighting to a Kessill A160 blue.
Current stocking is 2 clowns and 4 chromis. 1 cleaner shrimp, a few red legged hermits, trochus and narcissus snails. I have 2 rose BTA’s which do ok but haven’t really grown much in the last year (system will have been running for 2 years in October). Coral wise I have 2 pulsing Xenia which does great, a short polyp zoa which doesn’t open a great deal, some Kenyan Tree corals, another larger zoa which does good and a Duncan which I’m struggling with.
The Duncan did great initially then I moved it and it closed up. I moved it back and while there is some polyp extension it is short and nowhere near where it was when I got it first. I learned the hard way with my fish choices and have evicted a six line wrasse and a magenta dottyback as they terrorised the tank and killed a lot of fish (hence the current low stock).
I really want all the parameters where they should be before adding anything else and I’m taking the Duncans unhappiness as a good gauge.
My nitrates are high as a hangover of my previous overstocking, I’m combating this with Matrix and water changes. Phos is a little high as I run a reactor with Rowaphos which had stripped the Phos altogether (I took the reactor off in the last week to see if the Duncan responded but it didn’t) my plan is to put the reactor back on but lower the media amount so I can aim for around 0.04.
Feeding is a mix of pellets, frozen artemia, krill, spirulina and Read Sea coral feed liquid.
I've carried out a full test tonight and have the results as below. My main concern is the Alk, what’s the best way to raise it?
If someone could have a look at the overall readings and give me some pointers I’d really appreciate it! Thanks

Salinity 1.25
Temp 78.9
Phos 0.1
Nitrate 42.4
Ph 8
Alk 6.4 dKh
Calcium 430
Mag 1590

 

[nereefpat]

My main concern is the Alk, what’s the best way to raise it?

Alk of 6.4 dKH is lower than most of us keep it, but probably not dangerous. I would shoot for 7-8 range.

The easiest way to increase alk is using a solution of baking soda and RO water. If you wanted to raise from 6.4 to 7.4, for example, that would take about a teaspoon of baking soda. Dissolve 1 teaspoon in a cup of water and slowly add over a couple days. Then check alk afterwards.

If someone could have a look at the overall readings and give me some pointers I’d really appreciate it! Thanks

Salinity 1.25 - Assuming 1.025, fine.
Temp 78.9
Phos 0.1 - Fine, although a little high.
Nitrate 42.4 - I would try to get that to 20 or so with water changes.
Ph 8
Alk 6.4 dKh
Calcium 430 - fine
Mag 1590 - Fine, although a little high, but a little high on Mg doesn't seem to hurt anything.

 

[Spare time]

You find you alk dosage amount but seeing how much it dropped from one day to the next over a 24 hour period. You then adjust from there using whatever dosing product you choose to use. It's a good idea to test alk daily while figuring this out.

You have a few options

Use a 2-part, such as brs 2-part, esv b-ionic, or any other brand whereby you dose calcium and alk separately but in equal amounts.


Use an all in one. The most popular would be all for reef, but others such as salifert, and I think fauna marin have some. These contain Alk, calcium, magnesium, and trace/minor elements.

Use a calcium/alk all in one without the trace/minor elements (carbo-calcium by tropic marin)


Use kalkwasser. I'd avoid this if its your first time.

There are also other more advanced options that I don't recommend unless you hae serious experience with caustic chemicals

 

[TheXpander]

Thank you both very much, I’ll let you know how it goes