Help a newb learn 2 part dosing in large aquarium.

Miami Reef · May 16, 2021

First: I do not want automatic dosing. I want to do it all by hand. I don’t trust automated because it doesn’t disperse the amounts evenly and I don’t like the 2 part dosed into the sump.

Is there a way I can find out exactly how much I need to dose and do it once or twice a week?

I used to use 2 little fishies 2 part. Is there anything better? It’s pretty hard to find it, and I’m almost sure there’s cheaper options.

My problem is that I don’t know the exact volume of my tank. My tank isn’t a perfect rectangle, and even if it was, I don’t know how much rocks or sand. Nor do I know my sump volume. It hurts my head to think of trying to figure out the total volume. I guesstimate it at 300 gallons, but I honestly have no clue.

So, which 2 part is best for manual dosing? And how do I know how much to dose in a tank with undetermined volume?

zukihara · May 16, 2021

I am no expert but knowing the exact total volume is not going to help you. The rate at which your tank uses the things you are dosing is going to determine the amount that is best for you. You can always get a couple pumps and 2 part ESV and do it manually as you see fit, adjusting over time as you test the parameters.

redfishbluefish · May 16, 2021

There is no "best." They are all pretty much the same thing with minor differences. The least expensive would be using Randy's two part recipe. I recently figured it out that it cost me less than $3 per year for roughly 110 gallon system. The next would most likely be BRS two part system, which is based on Randy's formulas. After that, pick one....they're all the same. Manual versus dosing pump isn't even a factor in your choice. Also agree that total volume doesn't matter. Determine you demand and dose.

THIS ARTICLE explains two part dosing with a bend toward DIY. Initially you might be testing daily or multiple times a day, but once you get to know your tank and assuming no major changes with large additions of corals or clams, testing can back off considerable. I test about once a month or so and adjust my dose accordingly.

Miami Reef · May 16, 2021

Thank you!

blasterman · May 16, 2021

You dose according to how much your corals consume. Easiest way to determine this is to wait several days between dosing and see how much alk or calcium is required to get back to those levels.

Contrary to popular ignorance and lot of heavy industry marketing alkalinity and calcium are not consumed in specific ratios and only a tank full of rapidly growing SPS will make them one to one. A tank full of beginner frags won't consume enough calcium to bother testing. Sporadic water changing will easily replenish calcium. Alkalinity however is consumed by tank biology other than corals and will dive and change rapidly without any regard to what calcium is doing, especially in younger tanks.

Beginner tanks regardless of their size are mostly easily handled by letting occasional water changes handle calcium and magnesium and spot checking alk every couple of days. I use simple baking soda for alkalinity.

If / when your tank starts consuming enough calcium (my suggestion is 50 points less than your salt mix calcium level for starters) we can discuss. That's a long ways downstream.

You need to focus more on nutrient levels. Try to keep nitrate at 5-10 and phosphate around .03 without lots of algae blooms. This is the number one boo-boo young tank owners make.

Uncle99 · May 16, 2021

The more you spread that two part dose, the better for stability sake, that’s why the doser is a handy tool.
I dose 8 things, 1-3mls each hour, never missed in 4 years.
Hoe that’s just not luck.

Miami Reef · May 16, 2021

I purchased B-ionic 2 part. I dosed 75ml of Alk (1ml per 4 gallons of water). I didn’t use the calcium.

I waited about 10 minutes (didn’t give instructions how long to wait) and I tested the water...Alk is still 6.

I honestly expected that big dose to overdose the tank, but it didn’t do anything. The cloudiness only occurred when the Alk hit the water, but it instantly cleared up.

What should I do?

Uncle99 · May 16, 2021

Miami Reef said:
I purchased B-ionic 2 part. I dosed 75ml of Alk (1ml per 4 gallons of water). I didn’t use the calcium.

I waited about 10 minutes (didn’t give instructions how long to wait) and I tested the water...Alk is still 6.

I honestly expected that big dose to overdose the tank, but it didn’t do anything. The cloudiness only occurred when the Alk hit the water, but it instantly cleared up.

What should I do?

Is MG 1350-1450ppm.
If not, you’ll not get an accurate test.
What test kit?

redfishbluefish · May 16, 2021

Let's see what's going on. As @Uncle99 asked, what test kits? Also I'd like to know a little bit more about the tank....What salt are you using and at what salinity? How much hard coral and or clams do you have? That picture above appears to be light on corals....or they are small frags. It also would be great if you could have your LFS test your water or a local friend with their test kits so that your kit/method can be eliminated as the issue.

Miami Reef · May 16, 2021

Uncle99 said:
Is MG 1350-1450ppm.
If not, you’ll not get an accurate test.
What test kit?

I got 1270 with salifert just now.

API told me the alk result.

Miami Reef · May 16, 2021

I use ocean water. Salinity 1.026

The picture was prior to my addition of frags. Only soft corals and they are really small.

Uncle99 · May 16, 2021

That’s a bit low IMM.
API is the least accurate test for Alk, I would not use it.
Hanna Checker is fast and reliable.

redfishbluefish · May 16, 2021

Miami Reef said:
I use ocean water. Salinity 1.026

The picture was prior to my addition of frags. Only soft corals and they are really small.

What is the alkalinity of fresh ocean water? And I agree with API not being the best. If interested in wet chemistry Salifert and Red Sea are quality kits. Is your ocean water coming from a supplier or are you collecting yourself?

Miami Reef · May 16, 2021

redfishbluefish said:
What is the alkalinity of fresh ocean water? And I agree with API not being the best. If interested in wet chemistry Salifert and Red Sea are quality kits. Is your ocean water coming from a supplier or are you collecting yourself?

I get it from a supplier. He delivers is to most of the LFS’s in Miami. He’s been doing it for many years with a clean track record.

I never tested the water before adding it. I will do it to establish a base level. Excellent idea!

redfishbluefish · May 16, 2021

I agree...think this is a good starting point. Just so you know, soft corals don't consume alk and calc, so your demand should be very low, until such time you start adding LPS, SPS and clams.

And I am familiar with Florida using ocean water, especially with commercial accounts. The one I'd see actually drove out onto a pier and filtered the water through, what I think was, a diatom filter.