San Antonio Water Question

[dconyers]

Gents -
First, please understand I'm a newcomer to this hobby.

I have had a 42 Gal Tank for over a year and completed my first water change just a couple of hours ago. My tank is fish-only and there are only two of them(Purple Tang and a Tomato Clown). Previous to this point, I had always just added 'HEB Drinking/Distilled Water' to 'top-off' my tank. My nitrate level had exceeded my test kits chart (>100), and I've been considering adding a new fish (or maybe a piece of coral), so I decided to rectify this nitrate issue.

Now to the point - Yesteday morning I bought a 22 Gallon Bucket and rinsed it thoroughly with clean water. I then added 20 Gallons of Tap Water, Prime De-Chlorinator, Instant Ocean Sea Salt and Kent Marine Osmo-Prep. I placed a heater and small Rio pump in the bucket to heat and move the water. Last night, I tested the salinity and it was good, but the small pump wasn't moving the water very much, so I put two air stones connected to an air pump in the bottom of the bucket (this is probably the dumb, naive move). This morning the water looked great and tested fine, but when I came home this evening, I found a white coating lining the sides and bottom of the bucket as well as the pump and heater. It felt smooth (not gritty) to the touch and was easy to remove from the sides, etc. I retested the salinity and it was still fine, so I don't believe it was salt. It had no smell, so I dared to taste it and it had a chalky taste much like I had presumed (somewhat salty, but definitely not 100% salt). Anyway, can someone educate me as to what this stuff was and why it suddenly appeared and whether or not this is a good thing or something I should be concerned about? I did execute the water change, but I did my best not to touch the sides and get anymore of this stuff in my tank than was feasible.

Thanks in advance for the help - doug.

[captexas]

First water change in over a year?! :o Even with freshwater tanks you need to do water changes every so often even if you have a good filtration system going. You only have two fish in the tank which is somewhat of a light load for the tank, but over time the excess nutrients (uneaten food and fish wastes) continue to build up. If you don't have any live rock, a deep sand bed, or refugium on the tank then the only way to get rid of these is through water changes. I would recommend more frequent water changes and keep an eye on the levels before adding anything. As Josh asked, what else do you have in the tank? Live rock acts as an excellent filter system. If you add some to your tank, you need to make sure it is fully cured so you do not force your tank to cycle again and stress your fish.

Also, the white film you found when mixing the salt water happens sometimes when there is not enough circulation. The air stones probably didn't do much for circulation and just added a lot of oxygen to the water instead. Try mixing a smaller amount of water (changing 20 out of 42 gallons is too much at one time anyways) and hopefully your Rio will handle it better. If not, just get a bigger pump or add another power head to help the one you have.

Good luck and as Josh mentioned, welcome to MAAST and don't hesitate to ask any questions you may have.

[dconyers]

The information you both provided was very valuable - thanks.

Regarding the contents of my tank, it is a 42-hex, so I'm somewhat limited regarding the ability to easily add a refugium, protein skimmer, wet/dry filter or other recommendations that I found when reading through the forum archives.

My tank does have a 4-5" sandbed that I created based on a recommendation from Ken at AQSS in the middle of last year. I did this with the intent of managing the nitrate levels, though I'm a bit uncertain as to how effective this actually is. I installed the sand and then added some substrate from one of his live rock tanks. I also added 'Garf-Grunge' last month in hopes of additional seeding. I can see tiny air bubbles and 'pathways' when I look through the glass, but I'm still not certain if my sandbed is 'alive or dead'. Any insight would be appreciated. Also, I don't ever 'churn' the sandbed or anything else - is that correct?

Additionally, I have 30 snails and 15 hermit crabs from garf.org in order to address a nasty algae proliferation that I was suffering from. They seem to be happy in the tank, though I don't think they do anything but add to the nitrate problem.

Finally, I have an Emperor hang-on filter and just this weekend I replaced the stars in the gray basket with Kent's 'Nitrate Sponge' product. I believe it will be a long-term assistant in this area, though I don't think it will do anything in the short term. I use the standard blue pads in the filter and additionally I place 'floss' just before the blue pad to keep it clean so I don't have to replace it so often.

So, that's my current configuration. Do you see any obvious problems or areas of improvement? A gentleman at on of the LFS recommended that I consider adding some culerpa (sp?) to my tank, as it will address this problem. I have concerns that it might spread and become unsightly, though I have no experience with it. Do you guys think this is a good recommendation?

Much appreciated in advance. Hopefully someday I'll be able to contribute instead of just 'mooching' knowledge from you guys. I've been reading almost daily since I joined and have been extremely impressed with the information available.

Thanks again - doug.