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RO/DI Water Question - First Fill (1 Viewer)

abomb55076

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Duluth
So I started filling my 35gal tank last night with RO/DI water from my MPDI MaxPure System and realized how long it was going to really take me to get the tank filled going that route. I know it is perfect for the weekly water changes because I only need to do a bucket at a time but when I need 35gal, I'm looking for a better route. I saw that menards sells drinking water in 4gal jugs for fairly cheap, here. If it is distilled or RO, would this be ok to use? In my pico tank I use to use distilled water from the grocery store but I'm not sure if thats the correct way to do things, I believe thats only RO, not DI. Hoping to get the rest of it mixed and filled tonight so it can start to settle.
 
If you aren't putting in any SPS corals right away, in my opinion you will be fine to use the RO water from Menards (or Cub, Target, anywhere that sells RO water). I went this route for 9 months before I got my RO/DI filter, and I was keeping LPS corals and softies with no problem.
 
I would just learn that in this hobby you need to have patience, it will take awhile but in my opinion slow and steady brings success to the hobby. I'm sure that the other water would work, but if you already have the system just do it over a couple days.
 
So I started filling my 35gal tank last night with RO/DI water from my MPDI MaxPure System and realized how long it was going to really take me to get the tank filled going that route. I know it is perfect for the weekly water changes because I only need to do a bucket at a time but when I need 35gal, I'm looking for a better route. I saw that menards sells drinking water in 4gal jugs for fairly cheap, here. If it is distilled or RO, would this be ok to use? In my pico tank I use to use distilled water from the grocery store but I'm not sure if thats the correct way to do things, I believe thats only RO, not DI. Hoping to get the rest of it mixed and filled tonight so it can start to settle.

When I search for "MPDI MaxPure", most of the results are for 90 gallon per day units. So you should be looking at 8 hours to fill the tank. And even the slowest RO machines should have the tank mostly full by this evening. If you get home this evening and you still don't have enough water, there is most likely something very wrong with your RO setup and you should be posting more details about your RO setup so we can troubleshoot that.

But to answer your question, yes, water from the grocery or hardware store is fine. Even just straight up tap water (with dechlorinator) would be fine. During cycling/curing of the live rock the tiny amount of nutrients in less than 100% pure water relative to what is going to come off the rock is not going to make any difference at all. And you should probably plan to do at least one near-100% water change before you start stocking the tank with sensitive livestock anyway.

My prefered "shortcut" is to use the waste water from the RO machine. The waste water is already dechlorinated so it is safe to use as is and it comes out fast enough that mixing the salt will take as long as producing the water.
 
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When I search for "MPDI MaxPure", most of the results are for 90 gallon per day units. So you should be looking at 8 hours to fill the tank. And even the slowest RO machines should have the tank mostly full by this evening. If you get home this evening and you still don't have enough water, there is most likely something very wrong with your RO setup and you should be posting more details about your RO setup so we can troubleshoot that.

+1

I filled my 700 gallon system in just over a week. There's no way your tank should take more than 12 hours.
 
I believe I'm just going to purchase it from the LFS here in Duluth. They only charge .38 cents per gallon and its RO/DI 55ppm in and 0ppm out on their inline TDS meter. Yes, I have the 90 gpd system you found cypho, and I calculated just over nine hours to fill the tank, the only problem is I work 6am to 6pm m-f and have to sleep at some point too so I would have to wait until this weekend to get the water in there. I'm just excited to get it going! :freak6:
 
Heres another question... Should I mix the salt into the water before placing it in the tank or should I just mix the salt in once I get all the water in the tank? There isnt any live rock in the tank yet so I wouldnt have to worry about shocking the liverock with freshwater but I do have the Arag-Alive sand already in there.
 
Fill with water first then add the salt is perfectly fine for your situation. Ideally at least wait until water is room temperature ( even better if fully heated ) before adding the salt.

If you want to keep 35g of water on hand for emergencies, you can find 55g or smaller containers. You really want to use a container for storage anyways so that you can use a float valve for autoshutoff. So you don't have to worry about forgetting and let it run overnight while sleeping etc.
 
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I believe I'm just going to purchase it from the LFS here in Duluth. They only charge .38 cents per gallon and its RO/DI 55ppm in and 0ppm out on their inline TDS meter. Yes, I have the 90 gpd system you found cypho, and I calculated just over nine hours to fill the tank, the only problem is I work 6am to 6pm m-f and have to sleep at some point too so I would have to wait until this weekend to get the water in there. I'm just excited to get it going! :freak6:

Yes, it will take a while if you can only run the RO while you are watching. I assumed you were able to leave it running overnight or while you were at work. If you had left it running last night, the tank would have been full this morning. A float valve that can shut down the RO when the container (or tank) is full makes life a lot easier.

Heres another question... Should I mix the salt into the water before placing it in the tank or should I just mix the salt in once I get all the water in the tank? There isnt any live rock in the tank yet so I wouldnt have to worry about shocking the liverock with freshwater but I do have the Arag-Alive sand already in there.

You can do it, but I would not recommend it. It is hard to prevent ending up with big pockets of undissolved salt buried under the sand if you pour the salt in with the sand. You will have to stir the sand to get all of the salt out of it, and that will probably cause to water to become so cloudy you can't see anything in the tank for a while. If you have a sump or filter that you can add the salt to, that will work a lot better.
 
If you are going to get the water from a pet store do you already have containers? If so just fill them with r/o water in the bathtub. Then if they overflow no worries

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Buying ro/di may be the route I may take to avoid a massive water bill when I finally do my big build.
 
Massive Water Bill ? You get charge by the 1000gallons. Buying not only will 20X more expensive but a complete pain in the rear to transport.
 
Ahh ok I did not know that they charged per 1000 gallons. So maybe I won't buy,lol But I did when I had my 55g in 2013 and has no RO/DI and getting all that water in a shopping cart sucked and getting it to the car in slush was worse.
 

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