Big tanks a whole new world questions

[stingeragent]

Ok, so I'm about to start setting up the 125 I just got. Since it's drilled I'll be going back to a sump for anyone that saw my canister filter thread on my 40 (it's still doing great btw), but I'm about to enter into a new world of dosing, ato's, reactors, etc. I got an automated 4 pump doser with the tank, with a jug of mg, cal. Obviously I know I've gotta test before I dose, but im curious how you figure out how much to dose in relation to w/c's. Hypothetically lets say i do a water change on sunday. I wait a few hours and test for cal/mg/etc. My plan is to do another w/c the following sunday. What day do i check my water again for those elements to see what sort of dosing schedule I'd need? I'd guess the next sat, but the following day some will get replaced by that water change so should I shoot for middle of the week. Next is reactors. This tank will not be SPS heavy, so I can't see myself needing a carbon reactor. I know carbon/gfo combos are fairly common. Do these go in the sump, or do I have to plumb them outside of it? I have bags of phosguard, carbon, so how much more efficient are the reactors as opposed to just putting the bags in the sump? Lastly on that, I've read recently on algae scrubbers, would that be a better solution than the GFO? I already have the ATO that I've had for like 8 months now but I've never used it due to space concerns for the water resorvoir, but with me combining my 2 tanks into 1 , and the huge stand I'll finally be able to get that going. I've tested it and know how it works so no questions there. And to edit on the reactors, if they do go in the sump, do they require a constant water level like the skimmer? The sump I got with it is a decent size, but the skimmer is huge and won't have any room in that section for other equipment minus a heater. Not sure if it matters, but the tank will be mixed, softies/lps, but I did also get an acro (green slimer) with the tank, and may wanna get a couple more depending on how it does, but it will definitely not be a stick stank. I for once have time to get this tank up and running, and want to also for the first time, get it right the first time. Based upon what the tank will house as far as corals, what are the absolute must haves as far as what I've posted? I don't want to replumb the whole tank to put in a GFO if it's only a maybe it will be needed, but if it's a must have long term, I want to get in in now.

 

[thegrun]

As far as determining how much you need to dose I would test after your water change and then wait 4 days and test again. Divide the result by 4 and you get your daily dosing requirement. If you are using a controller and dosing pumps I would dose your alkalinity and calcium each hour throughout the day, so divide your daily requirement by 24 and you know how much to dose hourly.
If you plan on keeping a variety of corals I would argue you do need a carbon reactor to combat the toxins the corals release to fight off other corals for space. Yes you can just dump carbon in a bag, but I would guess it is at least twice as effective in a reactor. In my 120 gallon tank I have my reactors (carbon and GFO) mounted above the sump so it I have any plumbing leaks the water would simply fall back into the sump. I strongly recommend two individual reactors over a duel reactor as carbon and GFO do much better at different flow rates, carbon should not tumble, GFO should or it will quickly clog from calcium precipitation. I've seen some reefers simply set their reactors in the sump, but I prefer them out of the water. I prefer GFO over an algae scrubber simply because I don't want all the work related to maintaining a scrubber. Your reactor does not need a constant water level, it is either supplied by a separate pump of branched off the main return pump line (my preferred method as it eliminates more pumps that need to be maintained, assuming you size your return pump correctly).

 

[Sk8r]

x2 on waiting before testing. It takes time (8 to 24 hours) for a change to work its way through 100 gallons of water and reef. If you test before whatever has fully dissolved AND reached a uniform saturation throughout the reef--you will get an answer that could lead you to believe it's not enough yet: result: overdose.

You don't plumb in a gfo. They don't run except as needed, and dead or stopped equipment sitting around in a tank is an invitation to nitrate and worse. Just drop its pump into the return chamber and hang it on the sump edge: adjust.

You haven't mentioned your rock and sand, as important as the pipes. Cure the rock before using, if starting from dry. Wash the aragonite sand very thoroughly: it's a source of gunk if not. And this can take all day, sitting in the garden and washing it 5 lbs at a time. (More than that just compacts.) Use a garden hose, then dechlorinate with Prime. Do it now, while you have warm weather.

 

[stingeragent]

Ah ok thanks. So the GFO, you only run it if your actively having phosphate issues? The bulk of the rock will be from my established 55 and 40. Depending on the scape I may add 1 or 2 more pieces but I like the minimalist look. Just washed about 50 lbs of sand this morning, and got another 50 to go. I have 200 total but not sure how deep I want it yet. Yes washing that sand is a pain. Not really difficult but time consuming. As for the dosing, I wait 24 hours, and then measure, then wait 4 days. So lets say i started with 450. By day 4, it goes to 400. So then I would dose for 50 divided by 4? I'm assuming then, once I have that on a schedule, if I do my w/c sunday, take measurement the next day, then wait till thur to check again, and then start the dosing, so the following week, i do a w/c on sunday, by thur my level should still be 450 since I'm dosing now, but won't it drop off again between that thur-sun ? Or am I way overthinking this.

Edit: Ok wait, I think I'm starting to picture it. It will still be dosing between thur-sun, so theoretically on sunday it will still be 450 right? Wouldn't the water change then make it even higher