HEHE I love that little green alien. 90% of the time when someone types 1
flow rate that little bugger of an alien pops up. hehe
Yes that is per hour. For example on a 100 gal
tank the min flow for a reef tank should be 1000 gal
per hour flow rate. This is an approx figure so it needs not be an exact amount.
The truth is in a natural reef the flow rate is very high. It would be next to impossible to have to much flow in your tank.
Some corals need/like higher flows than other corals. Some corals wont open up at all under high current yet others will die unless they have good water flow.
I have an 80 gal
tank and I am running around 1200GPH flow rate.
You can measure flow by timing how long your overflow lines takes to fill up a known volume. So say it takes 15 sec to fill a 5 gal
bucket up to the approx 5 gal
mark. Since there are 4 sets of 15sec in a min if you multiply 5 * 4 you get 20 gal
per min flow rate. Since there are 60 min in an hour you take your 20 gal
flow per min and * 60 to get the flow per hour.
Most pumps will have a rated capacity of flow at a specific head height. For example a pump might be rated at 500GPH at 0' head. This means that as long as the pump does not have to push the water UP (against gravity) it will output approx 500 GPH
. But this same pump might be rated at 300GPH at 3' head. This means that it looses 200GPH flow rate due to having to push the water 3' above the pump. The higher the head the lower the flow as compared to the flow at 0' head.
Many pumps will have a flow to head chart.