HELP high nitrite levels and ick

[csimpson]

I have 3 Puffer fish all 3 in a 46 Gallon FOWLR tank set up about 2-3 months ago.
1- green spotted puffer about 3-3 1/2 inches long
1- Fiji puffer 3 1/2 inches long
1- valintini puffer 1 1/2 inches long
Water readings
Nitrate- 40
Nitrite- 5.0
alkalinity- 40
PH- 7.0

For a filter I have a marinelife emporer 280
for the last 2 weeks I have been fighting a nitrite spike and cant seem to keep it down I have been fighting it with Micro lift nite-out II hasn't really been helping. I went and got prime the day before yesterday june 4th and did a 20 % water change before I did that my nitrite level was 10.0 so I got it lowered down but cant seem to get it any lower then 5.0 I keep doing water changes but still not working. Now my Fiji puffer has ick and for a week now I have had my tank set up between 83-84 degrees and I can still see little spots on his fin. My other two don't seem to have it. Im at a loss with what to do? I have been told to get some live rock and im working on that but I don't have the money for that for about a month. can someone help me ? also I tested my sink water levels to see if that was the case and it read as fallows
Nitrate- 0
Nitrite- 0
hardness 300
chlorine 1.0
alkalinity- 40
PH- 7.2
I was thinking of setting up a hospital tank and putting the Fiji puffer in it but it is only a 6 gallon tank and right now I have have ghost shrimp and im breeding snails in it for the puffer fish. I know this is a small tank but I need to get him better. How would I go about setting up the hospital tank? should I clean out the filter in the 6 gallon tank or put a new filter cartridge in it? also can I treat him with "Quick cure" safely.

[bertie 83]

The nitrite will need to be diluted out by heavy water changes. I know little about crypt so best to wait for a pro to chime in.

[Master of Puffers]

what's the SG???

The valentini is a marine puffer..you need a SG of 1022-1026 for that alone..

[Master of Puffers]

what species is the Figi???

[RTR]

How much LR is in the tank right now? The readings imply that you are having bacterial nitrification, which in not normal with FOWLR unless the rock is uncured or insufficient or both.. The pH is quite low and implies that the tank needs much higher water change volumes. A larger tank is definitely desirable ASAP.

Is there a skimmer on the tank? And is it working?

[Pufferpunk]

Where did you get the rock & did you cure ALL of it before you added live animals to the system?

[Pufferpunk]

Where did you get the rock & did you cure ALL of it before you added live animals to the system?

[konesky]

I have read that an acceptable pH window for saltwater is 7.8-8.4 or so. Do you have access to reverse osmosis water to mix your saltwater with? That may solve your problem. What is your ammonia level?

[las]

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