Cycling my 115 gallon

Victor said:
are you sure it won't be too much of a shock?

i should do a gravel vaccum for the 30% water change too correct?

Yes it would be preferable to do a vacuum. And no Ime 50% water changes done weekly or bi-weekly will be fine, and doing them daily will keep the tank water at almost the same chemical composition, obviously there will be a little change due to a variety of factors, so daily changes would be preferable.
 
When you are cycling It could take up to 3 weeks to become reasonably clear, sometimes longer. It will depend on how quick your tank cycles, the only way to speed it up is to put bacterial established filter media in your new tanks filter.
 
Water changes is all you can do at this point. 0.3 nitrite is still dangerous, you should add some salt to help reduce the effects of the nitrite.
 
Nitrite level at about 0.1 ppm would require about 3 ppm of chloride ions. Salt has a chloride concentration of about 60%, so to prevent nitrite poisoning one teaspoon of salt would be sufficient to provide this effect for a 300g tank. So at 0.3ppm of nitrite you will need to triple this value, and ordinary table salt will be fine( Iodine wont matter in this amount).Btw increase airation in the tank.
 
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