Nitrates are less toxic than ammonia, but the catching and acclimating may be stressful for the Lion. If you can scoop him up easily and not stress him out too much, maybe the other tank would be best for now. If you think that’s not feasible, I’d recommend going with the prime detox method!I think 40 lbs and no I don’t have a skimmer or sub just the penguin filter I am going to invest in a skimmer soon I do have another tank the problem is nitrite is at 1 and nitrate is a 40 there is 0 ammonia in the other one should I put him in the other one or leave him