Help W/Specific Gravity and pH..

[Hypostomus]

Hello. I am helping my parents get a small tank ready for the introduction of some soft corals, but when I did a water test today I got some unsual results. We have never kept a saltwater tank before but have kept freshwater tanks for several years. Can anyone tell me what I should do to help stabilize the tank? Here's the stats:

20g
Running: ~1 month
Penguin 170 Biowheel Filter
ThermalCompact 100 watt Heater
~15 lbs live rock
"Sea Gravel" substrate- crushed white material (?)
1 ~8lb red rock (volcanic rock, I think)

1 false percula clownfish (Amphiprion ocellaris)
1 unidentified snail (3" shell diameter)

2x daily feedings (morning, evening)
-thawed brine shrimp, flakes, occasional Nature's Delica bloodworms

We have bought a Coralife "Aqualight" that consists of 2 fluorescent 65 watt bulbs (30"), fans, and a hood that we plan to install for the corals once we have them and a cleaning crew to deal with the algae.

The fish and the snail were adopted from a relative who could no longer care for them and are several years old. I am basing my identification of the clownfish on what I have found on the internet, though I do not know where to turn for the snail. I am going to take a picture of it and post it when I get back to school to see if someone can identify it for me. It appears to eat leftover food and I have not seen it go after any algae.

My mother did a water change yesterday of 2g with 1 cup of Deep Ocean sea salt added to each gallon. The water she used was tap water that had been sitting for a week, which was the method used by our relative when she had the fish. Today when I asked her about it I recommended that she just use the dechlorinator since we have plenty to spare. She also removed a plastic plant I had previously warned her about that I think may have something to do with our current problem.

Today when I did a water test I got the following readings:

("Sea Test" testing kit-- it's a few years old)
Ammonia - 0
Nitrite - 0
Nitrate - 25 [acronym:7b99cd4e6d="Parts per Million"]ppm[/acronym:7b99cd4e6d]
pH - 7.9
(Hydrometer appears to be a generic brand with a thermometer on the lower end)
Specific Gravity - 1.030
Temperature - 81 degrees F (this has been stable the entire time, according to my parents)

I'm assuming the plant might have been the cause, but could the water change have been off also? I was watching our unidentified snail and it closed up after the water change, refusing to move until this morning. Right now it is only waving its antennae around. The clownfish, since before we got it, has always been given to hovering right at the top of the tank and bobbing up and down. Since we moved it from its previous home it occasionally ventures down to have a look around, but then always goes back to the top of the tank. It does not "gasp for air," but simply hovers up there wiggling back and forth very energetically. It also stays toward one side of the tank, though I think the reason may be that the filter output flow is a little too strong.

The only time it goes really crazy is when someone approaches the tank (it has a glass lid and the clownfish immediately turns up to face whoever is looking in). Is this a problem that could be remedied when the corals are added or is something else amiss? The clownfish has a semicircular cut of its dorsal fin missing also, but it has been that way for years while my relative had it and I'm not sure why it hasn't grown back. However, it does not look diseased either. Any ideas?

To summarize my questions.. ( Sorry for the long post. )

-What could be causing my pH value to be so low and what's wrong with my salt density?
-What should I do to remedy these problems and stabilize the tank?
-How should I lower the nitrates? One source said I need the nitrates to be below 20 [acronym:7b99cd4e6d="Parts per Million"]ppm[/acronym:7b99cd4e6d] and then another said I need them below 5 [acronym:7b99cd4e6d="Parts per Million"]ppm[/acronym:7b99cd4e6d], and yet another said below .5 [acronym:7b99cd4e6d="Parts per Million"]ppm[/acronym:7b99cd4e6d]. The corals I was planning to get first were some mushroom corals (I'm not sure of the species- they are fleshy pink in hue), star polyp corals (there were green and yellow varieties available...again, I'm not sure of the exact species), and possibly some button corals. I definitely would like to stay with the soft corals because I need something that my parents can keep alive without me being there to check on the tank at every moment.

Thanks for your time.

[loganj]

Originally Posted by Hypostomus

-What could be causing my pH value to be so low and what's wrong with my salt density?

I'm not sure the pH is that low. I would suggest getting new test kits...either Salifert or Seachem. Since your kit is old, it may not be giving you correct readings. Your [acronym:bf28bbf68a="Specific gravity"]SG[/acronym:bf28bbf68a] should be about 1.025. 1 cup of salt per gallon seems a bit much to me. I use Instant Ocean and it calls for 1/2 cup per gallon.

-What should I do to remedy these problems and stabilize the tank?

I would get an alkalinity test kit in addition to the others. You may need to add some buffer to your water when you mix it up. The salt mix you're using may not be balanced correctly. You should also look into getting [acronym:bf28bbf68a="Reverse osmosis"]RO[/acronym:bf28bbf68a] or [acronym:bf28bbf68a="Reverse osmosis"]RO[/acronym:bf28bbf68a]/[acronym:bf28bbf68a="Deionization"]DI[/acronym:bf28bbf68a] water...tap water is generally bad for [acronym:bf28bbf68a="Saltwater"]SW[/acronym:bf28bbf68a] tanks.

-How should I lower the nitrates? One source said I need the nitrates to be below 20 [acronym:bf28bbf68a="Parts per Million"]ppm[/acronym:bf28bbf68a] and then another said I need them below 5 [acronym:bf28bbf68a="Parts per Million"]ppm[/acronym:bf28bbf68a], and yet another said below .5 [acronym:bf28bbf68a="Parts per Million"]ppm[/acronym:bf28bbf68a].

Again, look into the [acronym:bf28bbf68a="Reverse osmosis"]RO[/acronym:bf28bbf68a] water. Some tap water has nitrate in it. You could also add another 10lbs or so of [acronym:bf28bbf68a="Live rock"]LR[/acronym:bf28bbf68a] and remove the bio wheel. It is probably contributing to the nitrate levels. Regular water changes will help control it as well. For a reef tank, nitrates should be <10ppm with 0ppm being the target.

The corals I was planning to get first were some mushroom corals (I'm not sure of the species- they are fleshy pink in hue), star polyp corals (there were green and yellow varieties available...again, I'm not sure of the exact species), and possibly some button corals. I definitely would like to stay with the soft corals because I need something that my parents can keep alive without me being there to check on the tank at every moment.

While all the corals you have mentioned are fairly hardy, you need to get the nitrates and other water parameters under control before adding them.

[tkos]

I agree with removing the biowheel. Use the filter for water moevment. The biowheel is great for freshwater tanks but it creates lots of nitrates.

Also do you top off the water during the week with pure freshwater? If not then the salt concentration is probably getting higher.

[Hypostomus]

I checked the pH with a High Range pH Tester from my freshwater kit (far newer than the saltwater one) and it said the pH was at 8.2, perfectly stable from the last reading. I guess you were right about the old kit, so I'll pick up a new one. However, I tried a second hydrometer (same appearance and everything- I was just checking to see if the first one was off) and it still said the [acronym:ec972b1947="Specific gravity"]SG[/acronym:ec972b1947] was at 1.030. The snail isn't moving too much (though it is actively searching the area that it's in) and I was wondering if the high [acronym:ec972b1947="Specific gravity"]SG[/acronym:ec972b1947] could be a cause behind the clownfish's bobbing activity? Then again, I've noticed it will swim down if no one is near the tank and there's a bit of food on the bottom or something it wants to look at. And to answer that question- I don't know if my parents have been topping it off...but I'll ask them.

I'll call the [acronym:ec972b1947="Local Fish Store"]LFS[/acronym:ec972b1947] and see what they have for test kits and live rock, and I'll ask them about this to see how their advice compares. They keep all kinds of corals, anemones, other inverts, and fish there, so I trust them a great deal more than..say...the local Petco. They'll know about [acronym:ec972b1947="Reverse osmosis"]RO[/acronym:ec972b1947]/[acronym:ec972b1947="Deionization"]DI[/acronym:ec972b1947] stuff too, since I've seen units relating to that on sale there.

I can't believe a Biowheel is my enemy. :P

In order to keep Nitrates low...You may wanna cut back to feeding just once a day instead of twice.