Salinity

**Reefer0513** · 08-06-2010, 03:39 PM

What is the lowest salinity that marine fish can be keep in? What are the pros and cons to keep salinity low?

**rayme07** · 08-06-2010, 03:43 PM

I don't think its good for the fish to keep them in low salinity water for a long time. The only time it is good for the fish is when you are trying to get rid of ich and that is only for a short period of time.

**Amphibious** · 08-07-2010, 08:34 AM

I’m curious what prompts your question? What would you like to accomplish?

**Reefer0513** · 08-09-2010, 11:30 PM

The store I buy my fish and corals from told me that they keep their salinity in their holding tanks low below what other people keep their salinity. I was just wondering why they would do this and are there any benefits to doing so?

**Amphibious** · 08-10-2010, 01:05 AM

The theory is that parasites, such as Ich, are weaker at lower (hypo) salinity and have a shorter life span. That may be true but lowered salinity also has an effect on many other critters. Keeping lower salinity for long periods of time is not good marine aquarium husbandry. A better practice for LFSs and hobbyists would be to run a powerful UV on their system and keep the salinity at normal sea water levels of 35 ppm or 1.026 specific gravity. My advice is to not follow your LFSs example but, follow good husbandry.

Dick

**Reefer0513** · 08-11-2010, 01:18 PM

I have been waiting on my shipment of salt and it finally arrived today. I was wondering could I pre-mix saltwater in my auto top off container and let it replenish the salt that my skimmer is getting rid of as wastewater? or will this cause an imbalance in my system. My skimmer is setup with a drain and is for the most part wet skimming, which is causing my RO top off system to put straight RO water to continuously fill my sump up to keep my pumps from running dry and to replenish my water supply to my system, which is causing my salinity to drop very low to point I can not keep up with it manually. Right now my salinity is very low and I want to raise it slowly and was thinking this might be the way to do it without shocking my fish.

**Amphibious** · 08-11-2010, 06:14 PM

Wet skimming is toted as a benefit to skimming by some. The function of a skimmer is to concentrate what is being skimmed in the neck of the skimmer as a dry foam. It is then pushed up and into the collection cup. Wet skimming defeats the concentration effect and pushes salt water into the collection cup. Why would anyone do that on purpose??? It defeats the purpose of having a skimmer. Operate the skimmer as it is designed, to produce a dry foam, and pull that junk out of solution.

Use your ATO as it was designed, to add RO/DI water back into the system lost from evaporation.

Don’t try to reinvent the wheel or “fix” something that isn’t broken.

Dick

**CarmieJo** · 08-12-2010, 02:21 AM

I think it would be almost impossible to use your ATO to replace both the amount you are losing from wet skimming and evaporation. Evaporation is variable depending on temperature, humidity and the movement of air over the water. In addition, I don't know this for sure but I would be surprised if the amount you lose from skimming is constant.