And so it begins!!------72 gallon.

[Mooch28]

One thing that I saw pointed out in another forum (on the topic of using an RO/DI to fill a tank directly for top-offs) was that the initial bit of water that comes out of the RO/DI when it's first turned on each time will likely have a higher TDS than after it's been running for a bit. I don't have a TDS meter (need to get one), but I did notice a dramatically higher pH on the water that first comes out (I assume that means there's more "stuff" in the water). That's something to keep in mind if you plan to, every day or two, turn on the RO/DI to top-off... you'll always be adding the "not quite as good" startup water, compared to if you fill up a reservoir (in which case there would only be one dose of startup water, and it would be diluted with the better water that would follow). So, you might want to keep a bucket handy, let some water flow for a bit before actually doing the top-off. Or, as an alternative, use your 20g mixing tank as an RO/DI storage tank, either with an auto top-off float switch setup, or just a pump to manually add top-off water. Then, a few days prior to a planned PWC, you can stop using it for top-off water, use it for SW mixing, then go back to using it as FW storage.




Did you buy it local? If so, with no shipping, that's a great price indeed! And, if I'm not mistaken, that's a lot of rock! (isn't Haiti rock lighter than other rock?) That should fill up that tank nicely, and you'll probably have some leftovers for the sump.

--Mike

Your right. I have a TDS meter, and im getting 4 now, as opposed to 140 at first. But a lot of that was soder from welding pipes. PH was extremely low somwhere around 4 or 5, but i'll be running water for a week atleast before i fill the tank, and ive been flushing the system daily to get it stable.

As for rock, i bought it local from a guy that just opened a new store, and had an introductry price. He had 3000 LBS, but sold it off too me at 2.75 cents per pounds (actually not 3) since i bought so much. Worked out to 6 something, but he made it straight 600. Very nice guy. The rock it-self is dense, meaning you need more to fill up tank. But with 230 lbs, i should be able to support a ton of life!! And yes, it fills the tank right to the top, with some pices left for sump. I got real lucky on the rock!! Makes some very nice caves to this rock, since it comes in very odd shapes.

 

[Mooch28]

Guys, one thing.

Is it better to add sand after or before adding the rock. In other words, should rock sit ontop of sand, or should sand be placed around rock, while rock sits right on the glass??

Thanks agian.

 

[macphoto]

Your right. I have a TDS meter, and im getting 4 now, as opposed to 140 at first. But a lot of that was soder from welding pipes. PH was extremely low somwhere around 4 or 5, but i'll be running water for a week atleast before i fill the tank, and ive been flushing the system daily to get it stable.

From what I understand, it's not just the first startup of the unit after installation... every time you start it up, the TDS will be higher at first.

--Mike

 

[Mooch28]

From what I understand, it's not just the first startup of the unit after installation... every time you start it up, the TDS will be higher at first.

--Mike

Huum, not quite. The TDS in my unit has been low even at start-up. Luck maybe?? LOL!

 

[macphoto]

Huum, not quite. The TDS in my unit has been low even at start-up. Luck maybe?? LOL!

It's quite possible that I misread/misunderstood the comment... perhaps it does only apply to the first startup of the unit.

--Mike

 

[lbear]

I installed RO/DI for my new tank last week. TDS reading is 0 ppm almost from the very beginning. Input tap water is 270 ppm. However, I found the water pressure is low (about 40 psi) and ordered a booster pump.

Is it better to add sand after or before adding the rock. In other words, should rock sit ontop of sand, or should sand be placed around rock, while rock sits right on the glass??

I'd like to know too.

 

[macphoto]

Is it better to add sand after or before adding the rock. In other words, should rock sit ontop of sand, or should sand be placed around rock, while rock sits right on the glass??

The rock should definitely rest on the glass, so that it is stable and will not topple due to burrowing creatures or erosion from currents in the tank.

When I was at this phase, I wanted to put the sand in first, then the rock several days later. So, I ended up "digging in" the rocks, twisting and wiggling them so that they were touching (or very close to) the bottom. I also wedged in a few small rubble pieces under the rocks in some spots to provide additional stability. But, if you can put the rock in first, that's the best way.

--Mike

 

[Mooch28]

The rock should definitely rest on the glass, so that it is stable and will not topple due to burrowing creatures or erosion from currents in the tank.

When I was at this phase, I wanted to put the sand in first, then the rock several days later. So, I ended up "digging in" the rocks, twisting and wiggling them so that they were touching (or very close to) the bottom. I also wedged in a few small rubble pieces under the rocks in some spots to provide additional stability. But, if you can put the rock in first, that's the best way.

--Mike

I can put the rock first, and that is what i will do. I figured this would be the best way to get rocks sturdy, and not waste sand under rock.

Thanks Mike, you have been very helpfull!!

 

[Mooch28]

Well, tank has been delayed till friday (tomorrow), but i'll live. :

 

[macphoto]

I can put the rock first, and that is what i will do. I figured this would be the best way to get rocks sturdy, and not waste sand under rock.

Some people are more concerned about the opposite... they don't want to "waste" rock by having it buried under the sand (especially for a DSB), so they build little PVC platforms for the rock to sit on. But you have an abundance of rock, so it shouldn't be a problem!

Thanks Mike, you have been very helpfull!!

Glad to help!

--Mike