filling tank

[pugmommie]

In the next few weeks I am going to be filling my 120 gal for the 1st time.

I will have a closed loop. and 75 gal sump.
I have 3 holes drilled in back ( 1 closed loop and 2 to sump)
and 2 holes in bottom for closed loop.


When you filled your large tank for the first time did you use tap water, rodi, or rodi with salt?
Iam just worried about wasting if I have leaks.

Should I add sand after water? I'm thinking if I do have leaks it will be pain to fix bulkhead on bottom with sand in the way.

[der_wille_zur_macht]

Most people with really large tanks do a leak test with tap water before putting anything "real" in the tank.

Once everything looks good, you can drain the tap water and proceed as normal. Personally, my favorite approach is to add sand, then mix saltwater in another container and pump it into the tank. You can put a big plate on the sand to keep it from getting disturbed by the incoming water. Some people also put a garbage bag on the sand, under the plate.

[WrinkleFreeZone]

Definitely do a leak test before you add anything that you would regret losing.
-B

[EnglishRebel]

I have a related question. After doing a tap water test, how important is it to get all of the tap water out of the tank? Most pumps will leave some in the bottom. Should I use a wet/dry vac to suck out the rest? I'm concerned about the phosphates in the tap water.

[WrinkleFreeZone]

Drain what you can. Then take a towel and dry the rest. Yes, there will be a small amount of phosphate left behind from the tap water. However, the amount present in the tank in comparison to the volume of the system when RO/DI is added will be negligible. What's left is going to be rapidly consumed by the first algae blooms that everybody goes through.

The really big additions of phosphate are going to occur when you start feeding the tank assuming that you aren't using tap water for top off and water changes. If you are still in the planning stages of your system, consider a refugium to grow macro algae to aid with nutrient export.
-B

[pugmommie]

Thanks for the advice!