Originally Posted by
Sly
I find it curious that as soon as crushed coral was mentioned, people started looking at it as the culprit.
Fact, this is a new tank (recently cycled)
Fact, there is no live rock in the tank
Fact, there is no deep sand bed to make up for the lack of live rock
Fact, there are no plants in the tank
Fact, water changes are too small to be effective
Yet crushed coral is automatically to blame? (even though the tank is mostly sand)
A 10 gallon water change is about a 14% change. Every time you change the water this way, you dilute the amount of nitrate being removed from the tank. Just for reason's sake... If you pull out 10 grams of nitrate during the first water change, you will pull out only, say, 6 grams the next change. Then you pull out only 3 the next change. This happens because when you do a small change like this and you fill it back up with clean water, you dilute the nitrate so that when you change out the water again, you are taking out a mixture of clean and dirty water. In effect, you are diluting the amount of nitrate that you can remove at each change. It's an exponential decline. The more small water changes you do, the less nitrate you will pull out of the tank each time you do it. You want to pull out almost all of the nitrate but you will never be able to do it if you keep doing these small "maintenance" water changes.
You need to do a BIG water change. Do at least 50% and then throw in some activated carbon and some nitrasorb pads. Get some live rock ASAP. You have nothing in your tank that will consume nitrate and so it will just keep accumulating. If you have NOTHING to consume the nitrate, then it will build up very fast... even with a few small damsels.
Keep your system clean. Clean out any pre-filter pads regularly and get a good cleanup crew if you don't have one. This will help to clean up any extra food or junk in your tank. Extra food decays into ammonia and nitrate. Don't worry about the crushed coral. It adds variety to your tank. You could take it all out and still be in the same situation you are in now...
Change your maintenance patterns and get your tank properly stocked ASAP. Also, ditch that test kit. I used those and found that the nitrate and ammonia kit were always off from the other kits.
I would do ALL of the above and use RO/DI water. I have seen these little water filters work until their filter starts becoming a trate bed.