First Stages - Making Salt Water

[SparKy697]

I'm in the first stages of starting a 29 gallon reef tank with a 20 gallon sump. My LR is to arrive next week and I'm in the process of mixing SW to cure the rock in. After mixing Reef Crystals in a Rubbermaid tub with a power head/venturi for aeration and a heater I find that the water is cloudy even after the second day.

Is this normal? I did rinse out the tub a number of times and believe it to bee clean.

Here are some parameters:

Water: Using RO (not di at this time)

Water params: out of the RO unit Chlorine - 0, GH - 0, KH - 0, pH - 6.5

In the Tub the parameters are:

Temperature - 80 F

SG - 1.025

PH 7.7

I'm starting to think it is an issue with the tub I used. The pump has been shut off over night to see if the lack of agitation would help the cloudiness settle out, no change this morning.

Any suggestions?

 

[Ziggy953]

What kind of source water are you using?

 

[SparKy697]

Source is a municipal surface water system. Lake Michigan to be exact.

 

[Marconis]

Annnnd we're off.

 

[SparKy697]

Annnnd we're off.

Keep your fingers crossed Marco.

OK. The pump has been off all day. The water is clearing up. There is a white sediment layer developing on the bottom of the tub.

This leads me to believe that all of the sea crystals have not dissolved... The sg is good but why such a large amount of undissolved material?

 

[Hara]

the couple of batches of reef crystals that I tried were a pain to dissolve as well. I would suspect your salt mix as being the reason. I use oceanic and I have never seen a salt that dissolves nicer.

 

[SparKy697]

Ok, that makes sense.

My plans at the moment is to let the water sit until everything settles. Then draw off the clear water off of the top into a new vessel.

This seems to be a popular salt, what do others who use RC do to achieve better results?

 

[sayuncle]

RC and IO salts are crap.

 

[Innovator]

RC and IO salts are crap.

Very insightful. Anyways, all salt brands have negative and positive aspects to their products. Do a search at reefcentral.com and marinedepot.com/forums to research what salt brands are recommended and why

 

[Hara]

I believe there are also many threads here at AA on the same topic as well.

 

[zacusmaximus]

Um, is that pH right?

 

[SparKy697]

Um, is that pH right?

I'm sorry, that looked confusing. I fixed it.

The pH of the water coming out of the ro is 6.5. After adding the RC the pH in the tub is 7.7

HTH

 

[Hara]

still quite a bit too low..check it after it has been aerated for 24 hours and see what you get.

 

[Lance M.]

I mix RC with DI water and after about 1 minute of the powerhead going the water is crystal clear. I've never had problems with it not dissolving. Mine dissolves almost instantaneously.

 

[SparKy697]

I think we may have hit on something. I had only a small amount of ro in that tub. I put enough RC in for the amount of water I was planning on making and then let it fill up. Maybe next time I will let the tub fill up and then slowly add the salt....

EDIT 9/3/07:

I found an article this morning that explains exactly what I think happened. Under the title "How to Mix Artificial Seawater" the author gave an explanation of what I think happened: "Adding the salt before the water can be okay, but causes an unusually high salinity for the period when you are adding water, which can result in the formation of certain precipitates that may be hard to redissolve."

I mixed up a sample batch this morning by starting with the total amount of water and adding an appropriate amount of salt mix. Everything dissolved and left no cloudiness. For now I will say Problem Solved.

As far as pH goes, after a night of aeration the pH is still around 7.7. What should my target pH be and how should I get it there?

 

[roka64]

That pH is probably because you don't have enough surface ripple. Try adding a larger ph or point it to the surface. I use RC and prefer it over IO. I have never had a problem with it. I also keep a fresh batch of PWC going in a 32G bucket. Once you have mixed the salt in a few times, you will get the hang of how much salt to add to how much water.

 

[kay-bee19]

I mix RC with DI water and after about 1 minute of the powerhead going the water is crystal clear. I've never had problems with it not dissolving. Mine dissolves almost instantaneously.

I concur.

 

[Lance M.]

Yea SparKy697 I agree with the article you found to explain the cloudiness. When I mixed up the salt to catch my mantis shrimp, I put about 3 cups of salt in a gallon and half of water. The salinity was at least 1.040 and I couldnt see to the bottom of the bucket, about 5 inches deep, it was so cloudy.

 

[dskidmore]

As far as pH goes, after a night of aeration the pH is still around 7.7. What should my target pH be and how should I get it there?

This is probably because you don't have a DI unit. DI will remove charged particles that affect pH. Your live rock should help buffer the water. Are you also using argonite sand? If so, then I wouldn't worry until the whole setup is together and the pH is still low.

Do not add any pH up products. This is very hard to keep stable in the long run. Stability is more important than perfect parameters.

 

[roka64]

Dskidmore, I think the Joe is in the process of pre-mixing the water.