Need a little help.

Hi, I finally got my first reef tank going. I have 2 questions, first I have low salinty. Should I just throw a scoop of salt in every once in a while or premix it? Second how would you aim the power heads for the most flow? It's a 55 gallon long and I have 2 power heads.
Thanks

 

Never throw salt in without mixing it with water first. Also it shouldn't be necessary to add any salt to the tank once your salinity is correct. Adding fresh water for evaporation will be needed daily but the salt does not evaporate so your salinity will actually go up through the day.If you are not running a skimmer or sump it will be necessary for you to aim the powerheads up to the surface to get proper oxygenation of the water.

 

What kind of powerheads? If there koralias or if they can rotate I would put them on either side pointing at eachother and the front and pointed up a bit for surface agitation.

 

+1 110%

Also, you will want to raise your salinity slowly through normal water changes and/or by replacing evaporation with SW instead of fresh ro/di until you reach your target.

 

It depends on how low your salinity is. If it is really low, I'd take out 1/3 of the water, mix in enough to take it to 1.023, then add it back. Repeat every few hours until the salinity is correct. Don't ever bring your salinity up too quickly because it can kill your critters.

If it is only a little bit off, I would just add saltwater instead of RO water for topping off until it is correct. Then switch to RO water when it is correct.

Here's a wonderful article on salinity:
Everything you need to know about Salinity in a saltwater aquarium · Aquatic Digest - Aquariums

 

This is what I do. My salinity recently dropped due to my skimmer incident where a local earthquake dislodged the pump from the skimmer and it sprayed a lot of water all over the fish room. The lost water was made up by the ATO and the salinity dropped to about 1.021. I just used saltwater instead of fresh for top off until it got back up.

 

Well I think everything was covered. I always premix my salt in an extra tank I have to the salinity I want my tanks to be at. I've never had an issue with low salinity as of yet. As for the power heads, once you get corals is when you will really be concerned about this. As for now you want it to agitate the surface as stated above.