Water Testing results look grim:(

[jh2pizza]

ok, Out of desperation, I sent my water away to be tested. Now, before reviewing the results and jumping to conclusions, keep in mind a few things.

1. I use only Red Sea Coral Pro Salt. 450ppm CA tested.
2. My water volume is about 120 gals.
3. I have changed about 200 gals of water changes in the past 30 days at 15 gals a shot.
4. I use an RO system without the HiS membrane. That I know to change. and my water out of the DI is at 24ppm.
5. Have not dosed anything other than Randy's 2 part in a long time.

Silica 2.8 high I think I can solve that by switching to a HIS membrane.

potassium 309 low

ca 204 keep in mind all the water changes with 450 ppm salt

molybdenum .2 high I dose nothing other than Randy's 2 part and have not done that in the past 30 days.

Strontium 15.2 high

magnesium 1038 low

Iodine .02 low

Alk 3.62meq/l good

phosphates .01 Surprising


Where do I go from here? Its obvious, water changes are not curing the issues at hand.

[ufans]

24ppm TDS of your starting water is still quite high.

What is your pH?

If you have basically done a 100+% water change over 30 days and still have 204ppm Ca suggests that you are having a lot of Ca percipitation. Do you see any evidence of that?

Focus on the key factors: pH, Temp, Ca, PO4

Your real problem seems to be the Ca. The others could be explained for the lack of pure water via the RO/DI. Also, one test is not sufficient. Test kit and test procedure errors are common.

[demonsp]

Your changing water to often. By over doing the water changes you are causeing your tank to recycle. Never replace anymore then 33% at one time. 10% weekly or even 20% monthy depending on stock and water quality.

Also whene you add the new batch is it well circultated , like overnight before adding and do you add the new batch at a high rate?

[Billybeau1]

A tank will not recycle with large water changes. Biological filtration is not in the water column, it is on the rocks, sand and glass.

The first problem I see is your ro/di is not working properly for some reason. You should be getting zero tds out of your di. The silica removal is in the di cartridge, not the membrane. When is the last time you changed your sediment and carbon filters ?

Second, I think your calcium test kit is bad or you are not using it correctly. Mix up 1 gallon of new salt water at 1.026 and test it. Let us know what you get.

The rest of the results are of little concern at this point until you get the big three in check. Calcium, Alkalinity and Magnesium.

[bertoni]

I would confirm the measurements of calcium and magnesium, and dose those parameters to acceptable levels, probably over a few days.

I agree that the TDS meter might have a problem, or the DI cartridges might be shot. I'd calibrate the TDS meter and then test the tapwater, the output of the membrane before DI, and then the output from the DI again.

Low calcium with normal alkalinity is common if pH buffer products are used. How are calcium and alkalinity being dosed? What's going into the system?

The other numbers are okay, in my opinion.

[demonsp]

I would be concered with this quote , no ?



3. I have changed about 200 gals of water changes in the past 30 days at 15 gals a shot.

[murraycamp]

I agree with the above comments re test kits. When you said you sent a sample "away" to be tested, to whom did you send it? AWT?

Also, how did you test the Ca in the Red Sea Coral Pro Salt? Same methodology? I know that mix claims high calcium, but I am always skeptical. There can be considerable variance between batches as well.

[melev]

Originally posted by demonsp
I would be concered with this quote , no ?

3. I have changed about 200 gals of water changes in the past 30 days at 15 gals a shot.

It's fine. Have you read this article yet?
http://reefkeeping.com/issues/2005-10/rhf/index.php

[Boomer]

Yup, fine The only concern is in new tanks being cycled. I did 95 % WC /Month for 35 years with so such spikes. Bare bottom tanks are another issue, as they need all the nitrification they can get, as some does take place in the water column but not much and is easy to prove.


Joe and Jeni

I don't buy your AWT test results, UNLESS you are putting the salt in the container and then adding the water to it, which is a No-No. Then you will get low Ca++ and Mg++.

I think Billy is more right and it is the Ca++ test kit.

[Mark426]

demonsp,

You have been giving some crazy advice lately in a bunch of threads. I change a minimum of 20% of my water every week and have for the last 2 years. Granted I have a small nano tank and not a large tank....but I KNOW my tank does not recycle at every water change. Its doing great.

IMHO…a 20% water change or greater, every week would only be beneficial to ANY aquarium….its just not practical in a larger tanks. Thus the need for skimmers, reactors, dosing, etc.

Mark

[ReefNOut]

How are the corals doing? Do you have an extremely high demand on calcium? You probably just need to start dosing calcium and magnesium.

[drstupid]

when my mag is below 1200ppm, it's hard for me to keep calcium above 400ppm.

i don't know if i'd start with massive water changes and dosing to react to test results that are that far off, especially if your corals seem okay. i'd get a new kit first, at least borrow a friend's kit that they have been trusting.

you've got melev and boomer on the case now. don't worry, your problems will be solved before you know it.

[melev]

He's got Boomer at least.

[demonsp]

Yes it states only upto 50 % if circulated and airated.

The normally encountered differences in calcium, magnesium, alkalinity, nitrate, phosphate, silica, pH, etc., are unlikely to unduly stress organisms during water changes up to 30-50% using natural seawater or aerated artificial seawater, in my opinion.

[Boomer]

First, when you change water you should make sure those parameters are near that of the tank.

[melev]

Which I stated in this recent article:
http://reefkeeping.com/issues/2007-11/nftt/index.php