RODI lowering good parameters? Best way to get calcium and dKH up?

[bobpiker]

Here's my most recent tank parameters:

PH 8, AM 0, NO2 0, NO3 0, SAL 1.023, GRAV 30, dKH 7.85, CAL 360, ALK 2.8, PHOS 0, MAG 1125, TEMP 78-80, 55 gallon mixed reef, 5 gallon water change per week, reef crystals

I test with API for all parameters weekly, but have been using Salifert for PHOS, MAG and dKH/ALK for 2 months now.

Since mid-December, I've been using RODI for water changes and top-off. Four months prior just tap. Odd thing is that my calcium and dKH were within ideal parameters before starting with my new 4-stage rodi. Tap gave me 440 calcium consisently without additives and I never really had an algae problem of any kind. I've been trying to raise calcium and dKH ever since without a lot of luck.

Thinking I would just let the calcium raise slowly, I've been dripping kalk at a rate of about a quart per week. I suspect that isn't near enough, though, because it hasn't affected my calcium level after a month. My montis seem to be growing well (white edges--although I would like them to grow a bit faster).

As I prepare to set up my 112 gallon this spring/summer and get everything transferred over, I'd like to have better parameters there for several weeks beforehand and was hoping to be able to lock down better parameters in my 55 in order to make the aclimation easier

How do I get my calcium and dKH up? Should I just started dripping more kalk? Has anyone else noticed a drop in parameters once they started using a rodi?

Thanks,
Bob

[Benny Z]

it's not the ro/di water...just a natural progression of your tank consuming more than before.

i'd start dosing w/ a good 2-part solution - either a store-bought premixed formula, or diy 2-part w/ material from bulkreefsupply.

also, in an effort to minimize your testing routine, i would just test the following regularly:

dkh
calc
mag

you can test sg when you do water changes and give the temp a quick visual check, but those are really the only parameters you need to be testing once your tank is cycled. no3 and po4 are good to test, but testing po4 is never going to show up on a traditional test kit as it is consumed too quickly by algae. you need a low level photometer to test it accuately. no3 i'd test if you suspect it is creeping up, but if you have a dsb and/or are doing regular water changes it shouldn't be much of an issue...especially if you're testing it at 0 now...though i suspect it's not actually 0...again, a low level test kit is in order for accuracy here. but again, unnecessary as low levels of po3 are actually beneficial imo.

[bobpiker]

Hello, Benny Z.

Makes perfect sense that more calcium would be consumed as an aquarium "grows". I should have thought of that so thanks for clarifying it for me. It does get rather time-consuming with all those tests. At 8 months, I'm still a relative newb so I like your advice. I have a lot of xenia growth so I should be able to gauge some parameters with that, too. I'll keep testing dkh, calc and mag and keepy chaeto growing so that phosphates shouldn't be much concern.

What's your recommendation for a good 2-part?

Thanks, Bob

[twinspots_goby]

2 parts from Bulkreefsupply.

http://www.bulkreefsupply.com/store/products/calcium-alkalinity-magnesium/two-part-calcium-and-alkalinity-solution

[ReefnRod]

you said you dose a quart a week of lime water/kalk? i dose a gallon a day. 1/2 a table spoon a day with ro/di water. try to google randy holmes-farley and do some research on the chemisry of a reef tank. get an idea of why and how alk, calc and mag is used in reef tank.

[bobpiker]

Thanks, twinspots_goby. I'm ordering today.

Bob

[bobpiker]

Yep, I knew my dosing was low. I just wanted to see if I could register a change without having to mix a gallon everyday. No change, though. But I'll be going with an automatied doser soon enough and that should help a lot with 2-part.

Bob

[ReefnRod]

i agree! im saving for the bubble magus dosing pump.

[bobpiker]

Thanks everyone for the advice. After looking, do I understand correctly in that the Two Part Calcium and Alkalinity Total Package (Large) would make 7 to 8 gallons of calcium water. I'll look at the calculator but it sure seems like $70 for the total package isn't going to last long if using as a topoff. $40 a month for a gallon a day seems like a lot. Hopefully, the calculator at BRS will let me know that I shouldn't be dosing a gallon a day for a 55.

Bob

[Benny Z]

lol - you will be dosing milliliters, not gallons. it will last you months on end.

the calculator will help you figure that out quickly.

just use regular ro/di for topoff water.

cheers!!
- ben

[ReefnRod]

ya dont use that much. haha i dont use two part. when i said i use a gallon a day of kalk/lime water a day. thats a little bit of kalk in a gallon of ro/di for my evap. now, thats specific to my system and with what i do. your tank will be way different than mine. i always leave a litte to be desired when i make some statments. for alk i use baking soda also dosed with evap water. i alternate the them according to test results. so my 2 part is Mrs. Wages lime water and arm and hammers sodium bicarbonate with a dash of tedious testing. :)

[bobpiker]

Thanks for clearing that up for me. At first glance, it did seem like a lot and I was hopeful reading a bit more would clarify it for me. I'm off to the calculator today to find out exactly what I'll be dosing. Now for the pump...

Have a good weeked.
Bob